If the sleep, he shall do well - Sleep was regarded by the Jews, in sickness, as a favorable symptom; hence it was said among them, "Sleep in sickness is a sign of recovery, because it shows that the violence of the disease has abated" (Lightfoot). This seems to have been the meaning of the disciples. They intimated that if he had this symptom, there was no need of his going into Judea to restore him.

If he sleep, he shall do well - That is, if he sleep only, etc. Though the word sleep frequently meant death, (see Acts 7:60; 1 Corinthians 11:30; 1 Corinthians 15:18, 1 Corinthians 15:20), yet, as it was an ambiguous term, the disciples appear here to have mistaken its meaning. Because, in certain acute disorders, the composing the patient to rest was a favorable sign; therefore the words, If he sleep, he shall do well, or recover, became a proverbial forth of speech among the Jews. In most diseases, sleep is a very favorable prognostic: hence that saying of Menander: -

Ὑπνος δε πασης εϚιν ὑγιεια νοσου.

Sleep is a remedy for every disease.

See Grotius here. The meaning of the disciples seems to have been this: There can be no need for thee to go into Judea to awake our friend Lazarus; he will awake time enough, and his very sleep is a presage of his recovery: therefore do not hazard thy life by going.

Then said his disciples, Lord, if he sleep,.... Soundly, quietly, and comfortably, and takes rest in it:

he shall do well; or "be saved" from the disease; he will be delivered from it; he will recover out of it; it is a sign the distemper is leaving him, and he is growing better, and will be restored to his health again: the Ethiopic version renders it by many words, "he will be well", and "will awake", and "will live". Sound sleep is a sign of health. This they said to, put off their master from going into Judea, fearing the danger he would be exposed unto.

Shall do well (σωθήσεται)

Literally, shall be saved. Rev., he will recover. Wyc., shall be safe. Tyndale's Version of the New Testament, shall he do well enough.

Then said his disciples, Lord, if he sleep, he shall do well.

12. if he sleep, he shall do well-literally, "be preserved"; that is, recover. "Why then go to Judea?"

11:11-16 Since we are sure to rise again at the last, why should not the believing hope of that resurrection to eternal life, make it as easy for us to put off the body and die, as it is to put off our clothes and go to sleep? A true Christian, when he dies, does but sleep; he rests from the labours of the past day. Nay, herein death is better than sleep, that sleep is only a short rest, but death is the end of earthly cares and toils. The disciples thought that it was now needless for Christ to go to Lazarus, and expose himself and them. Thus we often hope that the good work we are called to do, will be done by some other hand, if there be peril in the doing of it. But when Christ raised Lazarus from the dead, many were brought to believe on him; and there was much done to make perfect the faith of those that believed. Let us go to him; death cannot separate from the love of Christ, nor put us out of the reach of his call. Like Thomas, in difficult times Christians should encourage one another. The dying of the Lord Jesus should make us willing to die whenever God calls us.