1 Corinthians 15:9-14

1 Corinthians 15:9-14. For I am the least of the apostles, that am not meet to be called an apostle, because I persecuted the church of God. But by the grace of God I am what I am: and his grace which was bestowed upon me was not in vain; but I laboured more abundantly than they all: yet not I; but the grace of God which was with me. Therefore whether it were I or they, so we preach, and so ye believed. Now if Christ be preached that he rose from the dead, how say some among you that there is no resurrection of the dead? But if there be no resurrection of the dead, then is Christ not risen: and if Christ be not risen, then is our preaching vain, the your faith is also vain.

It is all emptiness together. Our preaching evaporates-there is nothing left in it-unless Christ did really rise from the dead; and your faith has nothing in it either, you are believing in that which is only vanity, and nothingness unless his resurrection was a fact.