Matthew Poole and continuators on 1 Corinthians 15:6

6 After that he was seen of above five hundred brethren at once : of whom the greater part remain unto this present, but some are fallen asleep .

Of this appearance to above five hundred Brethren at once, the Gospels say nothing; but it is probably thought to be understood of that great Meeting of the Disciples in Galilee, where our Saviour promised to meet them, Matt. 26.32. & 28.7. after his Resurrection.

Where-ever it was, the Apostle saith, That the greater part of them were yet in a capacity to give a living Testimony to the Resurrection of Christ, though some of them were dead.