Albert Barnes Commentary 1 Corinthians 15:52

"in a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed." — 1 Corinthians 15:52 (ASV)

In a moment. en atomw. In an atom, namely, of time; a point of time which cannot be cut or divided (the 'a' being privative, and tomh from temnw, to cut). A single instant; immediately. It will be done instantaneously.

In the twinkling of an eye. This is an expression also denoting the least conceivable duration of time. The suddenness of the coming of the Lord Jesus is elsewhere compared to the coming of a thief in the night (2 Peter 3:10). The word rendered "twinkling" (riph, from riptw, to throw, cast) means a throw, cast, jerk, as of a stone; and then a jerk of the eye, that is, a wink.—Robinson.

At the last trump. This is when the trumpet will sound to raise the dead. The word "last" here does not imply that any trumpet will have been sounded before at the resurrection, but is a word denoting that this is the consummation or close of things; it will end the economy of this world and will be connected with the final state of things.

For the trumpet shall sound. See Barnes on Matthew 24:31.

And the dead shall be raised. See Barnes on John 5:25.