You remember is literally “you know” and implies that the general circumstances that led to Paul’s visit to Galatia are common knowledge among the Galatian Christians. He reminds them that it was because he was sick that he was enabled to preach the Good News to them the first time. In rendering the verb remember, it is important not to select a term which will suggest that the Galatians had themselves forgotten what had happened. It may therefore be better simply to translate you remember as “you know” or “you have known all along.”
It is possible to understand the sickness as simply something that afflicted Paul while he was preaching to the Galatians. This position is followed by some translators (for example, Phillips “you know how handicapped I was by illness when I first preached the Gospel to you”). However, most interpreters understand the sickness as the cause of his preaching there.
The nature of the infirmity has elicited numerous suggestions from scholars. Some connect the sickness with verse 14 and suggest a sickness that seriously affected Paul’s appearance and became a trial to the Galatian believers. But the illness may have been something which gave the impression that Paul was possessed by an evil spirit, pointing to epilepsy. Others connect the sickness with verse 15 and come to the conclusion that Paul had eye trouble. Others suggest that Paul contracted malaria while he was on the coast and had to travel up into Pisidian Antioch to recuperate. Still others connect it with the “thorn in the flesh” in 2 Corinthians 12.7. Finally, some claim that it was no physical sickness, but that Paul was referring to his sufferings when he brought the gospel to Galatia (compare Acts 14.19 ff.). Interesting and ingenious as all these suggestions may be, we still have to admit that we do not know the exact nature of Paul’s sickness. However, we can draw the conclusion that this sickness, whatever it was, was in some way offensive to the Galatians.
The expression translated the first time can be interpreted as implying a second visit (New English Bible margin “on the first of my two visits”). Some interpreters suggest that this second visit refers to the return journey of Paul on his way back to Syrian Antioch to conclude his first missionary journey, as recorded in Acts 14.21-28. It is possible, however, to understand the expression as referring to Paul’s original mission to the Galatians, and not to a second occasion, for example, “at the beginning, when the illness gave the opportunity” (New English Bible “it was bodily illness that originally led me to my bringing you the Gospel”).
Though it may be very convenient, as in Good News Translation, to separate the fact of preaching the gospel in Galatia from the reason for it, namely, Paul’s illness, and thus placing the two in separate clauses clearly marked by why and it was because, in some languages it may be much better to combine the two, for example, “You know that I preached the gospel to you the first time because I was sick.” However, in some languages it may seem very strange to combine sickness with preaching the gospel as reason and result or cause and effect. It may therefore be important to indicate that the sickness produced circumstances which somehow permitted Paul to preach the gospel, that is, that his sickness was the occasion rather than the reason for it. In this case, sickness would not be an immediate but secondary cause of his preaching the gospel, for example, “Because I was sick, it was possible for me to preach the gospel to you the first time,” or “My sickness caused the circumstances which made it possible for me to preach the gospel to you at first.”
Quoted with permission from Arichea, Daniel C. and Nida, Eugene A. A Handbook on Paul’s Letter to the Galatians. (UBS Handbook Series). New York: UBS, 1976. For this and other handbooks for translators see here .