Upvote:2
You are certainly thinking of 1 Corinthians 15: 4-7 where the Apostle St. Paul speaks about 500 eyewitnesses of which some were still living and names all the Apostles as witnesses also.
And that he was buried, and that he rose again the third day according to the scriptures: And that he was seen of Cephas, then of the twelve: 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. After that, he was seen of James; then of all the apostles. And last of all he was seen of me also, as of one born out of due time.