Why did Eutychus fall asleep? The physics of heating and ventilation

Acts 20:8-9 (NRSV) reads: "[Paul] continued speaking until midnight. There were many lamps in the room upstairs where we were meeting. A young man named Eutychus, who was sitting in the window, began to sink off into a deep sleep while Paul talked still longer. Overcome by sleep, he fell to the ground three floors below..."

Why does Luke mention the lamps? Did they contribute to the accident in some way? Some have suggested that the lamps made the air 'heavy' and that this made Eutychus sleepy, but I am not aware of any scientific assessment. Larkin suggests that "the boy must have tried to catch the night air by sitting on a windowsill". Haenchen and F.F.Bruce assumed that the air would be freshest by the window. But if the air was freshest there, why did he fall asleep?

I will argue that the lamps would have made the room comfortably warm and may have caused a soporific concentration of carbon dioxide in the air. I will also argue that the air may well have been more sleep-inducing at the window than elsewhere in the room.

Lamps produced a lot of heat and relatively little light. In a scientific experiment an oil lamp produced 60W of heat and only 10 lumens of light. A modern incandescent 60W light bulb produces the same heat, but gives 870 lumens of light. Along with its 60W of heat, the oil lamp produces 0.0084 cubic meters of carbon dioxide per hour. This is the same amount of heat and carbon dioxide as a typical person (modern adults produce 75W of sensible heat).

From what I can gather, upper floor rooms in insulae (apartment blocks) were typically 4m by 5m. We can imagine there being 20 people in the room and 30 oil lamps (or equivalent). The lamps would give a third of the light of a modern 60W bulb, so the room would still be dimly lit by our standards. Now, the people would then emit 1.2kW of heat and the lamps would produce 1.8kW, making a total of 3kW. Now, the incident occurred at the end of April or the beginning of May. At this time of year in nearby Istanbul the average daytime maximum temperature is 18C, and the nighttime minimum is 10C. Now, we do not know whether the room in question was constructed of brick or wood, so let us consider each case in turn.

Brick construction
Brick has a high volumetric heat capacity so the building's temperature will have varied little between day and night. The room will therefore have been at about 14C before the arrival of the large number of people and lamps. I have performed a computer simulation to calculate how much the room would warm with 3kW of heat starting at dusk (8pm). The model predicts that by midnight the effective temperature in the room would be a cozy 23C. Therefore the people and lamps are sure to have made the room comfortably warm and this may have contributed to Eutychus's drowsiness.

It is reasonable to suppose that they would have kept the door(s) and window(s) closed (for privacy and to avoid disturbing the neighbors) until the room had warmed up. I do not have a good estimate of what the natural air infiltration rate would have been. Well sealed modern buildings can give as little as 0.4 air changes per hour. If the room in question had 2 air changes per hour, the 30 lamps would have created a carbon dioxide (CO2) concentration of 4800 parts per million (ppm). This much CO2 could well have contributed to Eutychus's sleep since complaints of drowsiness occur at concentrations as low as 1000-2500 ppm. Also, since warm air rises, we should expect the CO2 concentration to be higher for Eutychus at the window, than for the others, who would have been at a lower level. Thus, it seems plausible that CO2 was a factor in inducing Eutychus's sleep. CO2 buildup would be possible only if the window was closed, but Eutychus would still fall out if the shutters or window covering were not secured. The image above is of carbonized wooden shutters in Herculaneum.

Wood construction
If the room in question was made of wood it is likely to have started the evening at a temperature above 14C since it would have gained heat from the outside during the day. It would also have warmed up quickly after the people and lamps arrived. By midnight the occupants would have needed to open the window(s) and perhaps door(s) to induce a considerable amount of ventilation to prevent over-heating. This ventilation would prevent a CO2 problem, but the temperature distribution in the room would be an issue. The through-draught needed to prevent over-heating would make the room cool at the end of the room where the fresh air entered, and warm at the end where the air left. Someone sitting at the warm end of the room might well start to feel sleepy and move to the nearest open window in search of cool air. Unfortunately the air in that window would be warmer, not cooler. To find the cool, fresh air, Eutychus would have needed to cross to the other side of the room where the cool air entered. Now, by midnight the ambient temperature will have been lower than the temperature of the air in the building, so there would have been a tendency for air to enter the building on the ground floor and rise by buoyancy and exit through the window on the third floor where Eutychus sat. Therefore, Eutychus is unlikely to have found fresh air at the window.

Conclusion
If the room was crowded, the window may have been the only available spot for Eutychus to sit. Alternatively, when he started to feel sleepy he may well have moved to the window in search of fresh air. Like Haenchen and Bruce, he may not have thought through the physics of air movement in a three floor building, for the air was probably warmer and richer in carbon dioxide at the window than elsewhere in the room. The heat produced by the lamps, and perhaps the carbon dioxide, will have helped to induce Eutychus's sleep and this may be why Luke mentions them.

Recommendations
To do a more thorough study we really need someone with expertise in ancient building architecture to collaborate with someone who is expert in thermal modeling of buildings and computational fluid dynamics (CFD). Any volunteers?

Epaenetus, Stephanas, and inscriptions

I argued here and here that Gaius Titius Justus was given the name/title "Stephanas" because he dedicated his house and household to the service of the church, and that Paul called him "Stephanas" when referring to him in connection with this benefaction (when writing to the Corinthians, who would have understood the significance of the name). Paul says that the household of Stephanas was the "firstfruits of Achaia" (1 Cor 16:15), and I argued that this signifies that Stephanas was the founding benefactor of the Corinthian church.

Now, Paul also describes Epaenetus as the "firstfruit of Asia for Christ" (Rom 16:5). Now, the name "Epaenetus", means "praised/commended", and, like "Stephanas", also belongs to the semantic field of benefaction. There are numerous inscriptions in which beneficiaries agree to "praise" a benefactor, and Rom 13:3 also appears to use the term in connection with benefactions (so Winter).

The connection between the names "Stephanas" and "Epaenetus" and benefaction is illustrated by an inscription from c24 C.E., in which a synagogue community honors a benefactor:

τοῖς ἄρχουσι καὶ τῷ πολιτεύματι τῶν ἐν Βερενίκῃ Ἰουδαίων ἐπαινέσαι τε αὐτὸν καὶ στεφανοῦν ὀνομαστὶ καθ᾽ ἑκάστην σύνοδον καὶ νουμηνίαν στεφάνωι ἐλαίνωι καὶ λημνίσκωι

the leaders and the politeuma of Judeans in Berenike decided to praise him, to crown him by name at each gathering and new moon with a crown of olive branches and ribbon, ...

Reynolds, Excavations at Sidi Khrebish Benghaxi (Berenice), vol. 1, 1977 p244, no. 17. Translation by Phil Harland (Associations, Synagogues, and Congregations).

All this raises the possibility that Epaenetus was the founding benefactor of the church in Asia and that Paul alludes to his benefaction in Rom 16:5 by calling him the "firstfruits", and by referring to him as "Epaenetus", the name/title that he had received for his benefaction. Perhaps he was Tyrannus (Acts 19:9).

It is surely no coincidence that both of Paul's "firstfruits", Stephanas and Epaenetus, have names that are suggestive of honors commonly given to benefactors, and that their names appear only in connection with their benefactions. This illustrates the practice of giving new names to benefactors in the early church (compare e.g. Joseph-Barnabas and Crispus-Sosthenes).

Book review of "Paul, His Letters, and Acts" by Thomas Phillips

In his 243 pages Phillips compares the Paul of the letters with the Paul of Acts. Instead of addressing Paul's theology, he focusses on Paul's "life", meaning his travels, chronology, and interactions with the Jerusalem church and others. These issues are central to any assessment of the historicity of Acts and for this reason Phillips' book deserves to be read.

Phillips starts by reviewing the Paul that Chilton reconstructs in Rabbi Paul, as well as the Paul of In Search of Paul, by Crossan and Reed. He then gives a useful summary of how the relationship between the Paul of the letters and the Paul of Acts has evolved, highlighting Baur and John Knox. However, I was disappointed that, having introduced the hypotheses of these authors, Phillips does not assess them.

Phillips rigorously follows a clear methodology for each topic. He first sets out the data found in the undisputed letters, then he does the same for Acts, and finally he compares the data sets. His approach is useful as it allows readers to make their own assessments. Scholars, who (rightly) focus on the apparent discrepancies between Acts and he letters, may be surprised at the degree of agreement between these texts. In chapter 3 Phillips applies his methodology to the chronological data. Chapter 4 concerns Paul's social status. Having equated Gal 2:1-10 with Acts 15, in chapter 5 he looks at Paul's relationship to the participants in this Jerusalem conference. In chapter 6 he assesses the data on the minor characters surrounding Paul.

In some ways Phillips gives a very balanced and cautious view. For example, he recognizes that there is considerable uncertainty in the social status of the Paul of the letters. However, on other occasions he is quite reckless. He attempts no careful exegesis of any passage, but simply assumes particular interpretations. This is unfortunate since his conclusion that there are discrepancies between the "two Pauls" relies almost entirely on ambiguous and much disputed passages in Galatians.

I noticed from the footnotes that he has clearly misunderstood modern writers on a number of occasions (e.g. p135 n25). There is a lot of repetition in the book, but it is readable, accessible, and worth the US $24.95.

Paul's visits to Troas

How Acts 16:6-11 explains 2 Cor 2:12-13
In Acts 16:6-11 we read that Paul and his companions were not permitted to preach in the province of Asia, which included Troas. They arrived in Troas but immediately are called to Macedonia. Evidently, they did not evangelize Troas or indeed its region, the Troad.

In 2 Cor 2:12-13 we learn that Paul's anxious desire to meet Titus drove him from the Troad to Macedonia. Paul had presumably communicated his Ephesus-Troad-Macedonia travel plan to Titus, who was to leave Corinth and travel to wherever Paul was scheduled to be at the time. Paul therefore knew that Titus would not arrive in Troas after the date that Paul had been due to leave. Paul, proceeded to Macedonia when this date passed because he was anxious to meet Titus as soon as possible. Paul had to stick to his original schedule to meet Titus the soonest. Now, Paul writes that he had gone to the Troad to evangelize and that a door was opened for him. The implication is that an unexpected opportunity for evangelism had arisen and that, had it not been for his anxiety, he would have extended his stay in the Troad beyond his scheduled departure date to exploit this opportunity. This makes it rather likely that Paul had not previously evangelized the Troad. If he had done so, he would have known what to expect and he would have been better able to judge how long he would wish to devote to that region. The opening of the door was unexpected because he had not tried that door before.

So, there is a minor point of agreement here between Acts and 2 Corinthians. Both imply that Paul did not preach in the Troad on his way to Macedonia.

How 2 Cor 2:12-13 explains Acts 20:6
When Paul went to Troas for the third time his desire to preach there was so strong that he spoke until midnight (Acts 20:7) and continued to converse until dawn (Acts 20:11), when he left for a full day's journey to Assos without having slept at all. He also devoted o fewer than 7 days to Troas (Acts 20:6), even though he was in a hurry to reach Jerusalem (Acts 20:16)? Haenchen thought that Paul had difficulty finding a ship, and Pervo also suggests that the delay in Troas was involuntary, but this extended stay in Troas is simply explained by the priority that Paul placed on preaching in Troas.

All this agrees well with 2 Cor 2:12-13, which tell us that, a few months earlier, Paul had had to leave the Troad in a hurry, leaving preaching opportunities unexploited. It makes sense that Paul would want to spend a week in Troas to complete the work that he had cut short the previous year.

Acts and 2 Corinthians are in harmony here too.

The commentators seem to have missed these points.

Acts 24:17, the collection, and Ananias

Acts 24:17 reads:

"Now after some years I came to bring alms to my nation and to offer sacrifices" (NRSV)

Now, Downs (correctly) argues that the bringing of alms here sounds more like an act of private piety than the delivery of the collection that Paul had organized from the churches of Achaia and Macedonia ("Paul’s Collection and the Book of Acts Revisited" NTS 52 2006 p50-70). Luke's Paul is here presenting the collection as an act of private piety. Why did he do so? Well, I argued in my last blog post that the collection had been prohibited by the Jews of Achaia, who had jurisdiction in such matters, and that it was therefore illegal or at least controversial. It seems to me that this neatly explains why Paul presents the collection as an uncontroversial act of private piety. Paul, on trial for his life, choses his words carefully, preempting any accusation his accusers might bring about the collection.

Luke did not want to draw attention to the fact that the Christians had defied authority, so he did not reveal that Paul had collected funds from Galatia and later from Macedonia and Achaia. He was comfortable to mention only the uncontroversial famine relief by the church of Antioch (Acts 11:27-30) and Paul's carefully chosen words about bringing alms to Jerusalem. I suspect that Luke was cautious because adversaries of the church could get hold of a copy of Acts. Luke's intended audience, on the other hand, may have already known about the collection, in which case they would have understood the significance of Acts 24:17.

Apart from Acts 24:17, do we have other examples of cases where Luke's Paul carefully choses his words to save his skin? I would like to bring up one example. In Acts 22:1-3 Paul stresses his own strict Jewish credentials, and upbringing at the feet of Gamaliel. Luke here is not making the claim that Gamaliel was Paul's only teacher, or even his main teacher, as many suppose. Under the circumstances it would be legitimate for Paul to be selective with the facts. Remember that this is Luke's account of Paul's words, not Luke's account of events. Then, at Acts 22:12-15 Paul gives not hint that Ananias was a Christian, but says that he was devout according to the Law and respected by the Jews, and that he had endorsed Paul's future work. This information is completely absent from Luke's account of the same events in Acts 9:10-17. In Acts 22:12-15 Paul is seeking support from his audience by claiming that his work had the backing of a devout Jew. Luke's Paul, in great danger, understandably chooses his words carefully to try to win over his hearers.

We cannot, of course, prove that Acts 24:17 and Acts 22:1-3,12-15 are not Lucan invention, but it seems to me that these claims to Jewish piety are just the kinds of things that we would expect Paul to say, given the circumstances.

The plot against Paul (Acts 20:3)

We read in Acts 20:3 that the Jews made a plot against Paul when he was about to set sail for Syria. I will argue that the plot is historical and that it consisted of the decision by the Jews to intercept Paul if he attempted to deliver the collection. Points 3, 4, 5, and 8, are new.

1. Paul nowhere identifies anyone who helped with the collection. The two 'brothers' in 2 Cor 8:18-24 and the 'brother' of 2 Cor 12:18 are strangely anonymous, and Paul conspicuously uses Timothy's lesser-known name (Titus) when discussing him in connection to his missions to organize the collection. These silences are explicable if Paul was aware of opposition to the collection and was worried that it would be endangered if the identities of the helpers would leak out.

2. The plot was when Paul was about to sail. This is historically plausible since only at that time would it have been possible for the Jews to attempt to intercept the collection. Before that time the collection was dispersed in the homes of the individual donors (see 1 Cor 16:2).

3. If the plot was to attack Paul's person, it is surprising that he found out about it. If, on the other hand, Paul had been publicly forbidden from delivering the collection, he would have had reason to suspect that he would be under surveillance. Paul's knowledge of the "plot" is then explicable.

4. If the Jews (who had been given jurisdiction by Gallio) had declared the collection illegal, it would have been too dangerous for Paul to return to the Aegean after delivering the collection, and this would explain why Paul knew that he would not see the Ephesians again (Acts 20:25). The collection's illegality also explains why Acts does not mention it (for Luke is always careful to avoid giving any hint that the Christians do anything illegal).

5. We read that to avoid the plot Paul went north to Macedonia (Acts 20:3) and he sailed from Philippi and stayed in Troas (Acts 20:5). Why Philippi and Troas, rather than, for example, Beroea, Thesssalonica, or Ephesus? This was a long diversion, given his tight schedule (Acts 20:16). Well, it occurs to me that Philippi and Troas are the cities where he would have been safest from the plot of the Jews. We have no evidence of a synagogue in Philippi, and Acts records no Jewish opposition to Paul there. Also, there is no evidence that there were Jews in Troas in the first century.

6. Jewett argues that the boat that Paul took from Philippi to Patara was probably a coastal freighter that he had obtained for his exclusive use. This would have avoided the risk of being betrayed by fellow-passengers or port officials.

7. Paul's decision to split the party (Acts 20:5) will have served to protect the collection (so Gilchrist). The delegates (who were not under suspicion) would have been able to carry the collection with little risk of ambush, while Paul and Luke travelled separately with their empty pockets hanging out. Paul also travelled independently to Assos (Acts 20:13-14) and this also makes sense as a precaution against being arrested or ambushed while boarding a boat with the collection.

8. At first sight it seems that this "we" passage gives a surprisingly detailed and boring account of the journey. However, if the intended readers were expected to know that Paul was in danger of arrest or ambush, this passage is a gripping account of a daring escape and its inclusion is explicable.

It seems to me that the contents of this "We passage" comport well with the preceding mention of the plot (Acts 20:3). It is hard to imagine that Luke has inserted someone else's travel diary into his text at this point, as many suppose.

In summary: Paul, knowing that the collection would be opposed by synagogue Jews, chose to protect the identities of those who were to deliver it. The Jews in Achaia forbid Paul from delivering the collection, but he chose to do so anyway, even though he knew that he would be arrested if he ever returned to the Aegean. He was aware that he was under suspicion and that if he took a boat heading east he could be betrayed by crew or fellow passengers. He therefore headed north to Philippi, where there were few, if any, Jews who opposed him. Knowing that he was under more suspicion than the delegates, he sent them ahead to Troas with the money. Later, he walked from Troas to Assos, as a diversionary tactic, while the others took the money in the boat. To avoid being betrayed by fellow passengers they chartered a coastal freighter for their private use. Luke did not want to mention the collection in writing because of its illegality (Acts might fall into the hands of opponents), but his intended readers probably already knew about it. He wrote a dramatic account of how he and the others smuggled the collection out of the Aegean.