Contradiction with John 18:20
This verse has Jesus saying He taught openly to the world and not in secret, which contradicts Acts 10:41 suggesting He was shown only to chosen witnesses.
John 18:20: Jesus answered him, I spake openly to the world; I ever taught in the synagogue, and in the temple, whither the Jews always resort; and in secret have I said nothing.
Contradiction with Matthew 28:19
Here, the disciples are instructed to teach all nations, contradicting Acts 10:41 where Jesus appeared to select witnesses rather than openly to all.
Matthew 28:19: Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost: [teach...: or, make disciples, or, Christians of all nations]
Contradiction with 1 Corinthians 15:6
This verse mentions Jesus being seen by over 500 people at once, contrasting with Acts 10:41 which implies He was shown to a limited group.
1 Corinthians 15:6: 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.