Expositor's Bible Commentary Commentary John 11:4

"But when Jesus heard it, he said, This sickness is not unto death, but for the glory of God, that the Son of God may be glorified thereby." — John 11:4 (ASV)

Jesus’ reaction was optimistic and purposeful. He gave assurance to the disciples that Lazarus’s illness would not terminate in death, and stated that Lazarus’s illness would be an important aspect of his own glorification. Having said that, he deliberately stayed in Perea two more days. His action may have appeared to the disciples, and almost certainly to the sisters, as unfeeling and selfish. Since he had the power to heal Lazarus, why should he not reply instantly (cf. Lk 7:11-16; 8:41–42, 49-56)? Perhaps the disciples were not particularly puzzled, for their subsequent remarks indicated that they were well aware of the danger that threatened him in Jerusalem.