Barnes New Testament Notes

Verse 10. Who died for us. That is, to redeem us. He designed by his death that we should ultimately live with him; and this effect of his death could be secured only as it was an atoning sacrifice.

Whether we wake or sleep. Whether we are found among the living or the dead when he comes. The object here is to show that the cone class would have no advantage over the other. This was designed to calm their minds in their trials, and to correct an error which seems to have prevailed in the belief that those who were found alive when he should return, would have some priority over those who were dead. See Barnes "1 Th 4:13"

and following. The word rendered "together", ama is not to be regarded as connected with the phrase "with him" -- as meaning that he and they would be "together" but it refers to those who "wake and those who sleep" -- those who are alive and those who are dead -- meaning that they would be together, or would be with the Lord at the same time; there would be no priority or precedence. Rosenmuller.

{d} "whether we wake or sleep" Ro 14:8,9; 2 Co 5:15