Yes indeed the Bible is very clear about not getting married / yoked with unbelievers..

(2 Corinthians 6:14-16) "Be ye not unequally yoked together with unbelievers: for what fellowship hath righteousness with unrighteousness? and what communion hath light with darkness? {15} And what concord hath Christ with Belial? or what part hath he that believeth with an infidel? {16} And what agreement hath the temple of God with idols? for ye are the temple of the living God; as God hath said, I will dwell in them, and walk in them; and I will be their God, and they shall be my people."