1 Corinthians 15:12

But if Christ is preached as having risen from the dead, how is it that some of you say that there is no such thing as a resurrection of the dead?

For the Sadducees maintain that there is no resurrection, and neither angel nor spirit; but the Pharisees acknowledge the existence of both.

In the matter of the truth they have gone astray, saying that the Resurrection is already past, and so they are overthrowing the faith of some.

When they heard Paul speak of a resurrection of dead men, some began to scoff. But others said, "We will hear you again on that subject."

Why is it deemed with all of you a thing past belief if God raises the dead to life?

If there is no such thing as a resurrection of the dead, then Christ Himself has not risen to life.

comfort your hearts and make you stedfast in every good work and word.

Treasury of Scripture Knowledge

Now if Christ be preached that he rose from the dead, how say some among you that there is no resurrection of the dead?

that He was buried; that He rose to life again on the third day in accordance with the Scriptures,