His disciples replied, “Lord, if he sleeps, he will get better.”
One of the signs of recovery from sickness was sleep. Morris points out that the disciples were probably quite ready to come to this conclusion because it would remove the necessity for the dangerous journey to Judea.
Interestingly, the words “do well” are the translation of the Greek word “sozo” which means to be made whole or to be saved. There may be a secondary meaning involved here as to the salvation of believers who “sleep”.