I can't see a problem with sex before marriage myself, but thats just my opinion.

Considering I don't think sex before marriage is wrong, I'd definitely have to say sex outside of marriage is worse. Cheating on your spouse or any partner for that matter is an extremely hurtful thing to do someone, whereas sex (assuming it is consensual) can be a mutually pleasurable act that is not directly hurting anyone...I don't know, personally, I really don't think the two acts are even comparable

Marrieage is so sinnful it is worse. But really, what kind of wimp, claims to be faithful until death and isn't.

i believe they are on an equal footing as bad

i firmly believe in what God's inspired word the bible has to say on the matter. any kind of sex outside of marriage is wrong. a person who has sex without the benefit of marriage is committing a gross sin in the eyes of God. in the eyes of God this is illicit sex relations outside of Scriptural marriage. the hebrew verb zanah and its related forms convey the idea of harlotry, immoral intercourse, fornication or prostitution. (genesis 38:24, exodus 34:15, hosea 1:2, Leviticus 19:29) the greek word translated "fornication" is porneia. regarding the meanings of porneia, b.f. westcott in his book saint paul's epistle to the ephesians says: tis is a general term for all unlawful intercourse. bauers grek-english lexicon of he new testament defines porneia as "prostitution, unchastity, fornication, of every kind of unlawful sexul intercourse." porneia is undrstood to involve the grossly immoral use of the genital organs of at least one human; also there must have been two or more parties (including another consenting human or a beast), whether of the same sex or the opposite sex (jude 7) the unlawful act of a rapist is fornication, but, of course, that does not make the person who is forcibly raped also a fornicator. when God performed the first human marriage he said: "that is why a man will leave his father and mother and he must stick to his wife and they must become one flesh." (genesis 2:24) here the standard for man and woman was monogamy, and promiscuous sex relationship was ruled out. also, no divorce and remarriage to another was anticipated. in patriarchial society god's faithful serveants hated fornication, whether between single, engaged, or married persons, and it was considered a sin against God. (Genesis 34:1,2,6,7,31; 38:24-26; 39:7-9) jesus christ showed the wickedness of fornication by classing it with murder, thievery, wicked reasoning, false testimony, and blasphemy. he pointed out that these come from within a man, from his heart, and defile him. (matthew 15:19,20; Mark 7:21-23) later the governing body of the christian congregation, comprised of the apostles and older men in jerusalem, wrote to christians in about 49 c.e., (common era) warning them against fornication, and placing it alongside idolatry and the eating of blood. (acts 15:20,29; 21:25). the apostle paul points out that fornication is one of the works of the flesh, the opposite of the fruitage of the spirit of God, and warns that the practice of fleshly works wil prevent an individual from inheriting the kingdom. (galatians 5:19-21) he counsels that the christian should deaden his body "as respects fornication." (colossians 3:5) in fact, he warns that it should not even be a topic of conversation among christians, who should be holy.