Where in the bible does it say that if you cant abstain from sex and spread the word then do so but if you cant then be married?

The reference you're looking for is in 1 Corinthians 7:9, where the Apostle Paul advises that if someone cannot control their desires, it is better for them to marry than to burn with passion. He emphasizes the importance of marriage as a solution for those struggling with sexual temptation, suggesting that it is better to engage in a marital relationship than to remain single and face the challenges of abstaining.