John Calvin Commentary Luke 2:29

"Now lettest thou thy servant depart, Lord, According to thy word, in peace;" — Luke 2:29 (ASV)

You now send your servant away. From this song it is sufficiently evident that Simeon looked at the Son of God with different eyes than the eyes of flesh. For the outward sight of Christ could have produced no feeling but contempt, or, at least, would never have given such satisfaction to the holy man's mind as to make him joyful and desire to die, because he had reached the height of his desires.

The Spirit of God enlightened his eyes by faith, so that he perceived the glory of the Son of God under a humble and poor appearance. He says that he would be sent away in peace; this means that he would die with a composed mind, having obtained all that he desired.

But here a question arises. If he chose rather to depart from life, was Simeon hurried away amidst distress of mind and murmuring, as is usually the case with those who die unwillingly? I answer: we must pay attention to the circumstance that is added, according to your word.

God had promised that Simeon would see His Son. He had good reason to continue in a state of suspense, and must have lived with some anxiety, until he obtained what he expected.

This should be carefully observed. For there are many who falsely and improperly use Simeon's example, boasting that they would willingly die if this or that were previously granted to them. They do this while allowing themselves to entertain rash wishes according to their own desires, or to form empty expectations without the authority of the Word of God.

If Simeon had said exactly, "Now I will die with a composed and easy mind, because I have seen the Son of God," this expression would have indicated the weakness of his faith. But, since he had the word, he might have refused to die until the coming of Christ.