A friend sent me this quotation:

At this point the objection will come up: “What? John writes that every one should lay down his life for his brother (1 John 3:16). Therefore when we know and see that the members of Christ are shut up in prison, it is not right to desert them by fleeing while we look out for our own safety and are not touched by the suffering of our afflicted brethren.”  Here we have to make a distinction: the death of our neighbor is either bodily or spiritual. If we are talking about the corporal or external death of our neighbors, in my judgment we do not always have to lay down our corporal life for them-something I could confirm with both many examples and also arguments. But if we are dealing with the spiritual death of a brother, one should indeed die if by his bodily death one can help him so that he does not perish for eternity. On this basis Christ died for us; it will be the disciples’ task to imitate the master himself. Therefore if someone has a sure hope that he will be able to help a brother by his presence, encouragement, and consolation so that he does not fall into eternal destruction, he ought to remain even if he does it at the risk of his life and, as the Scripture requires, he lays down his corporeal life for his brother’s eternal salvation.

Peter Martyr Vermigli, “Letter No. 5 On Flight in Persecution,” in Life, Letters and Sermons, trans., by John Patrick Donnelly, (Kirksville, Missouri: Sixteenth Century Essays and Studies, 1999), vol 5, pp., 83-84.