The Bible teaches us that God has reserved all forms of sexual activity as His gift to those who join to one another in marriage covenant relationship. As such, any sexual act performed before marriage is considered sexual immorality, is strictly prohibited and serious sin. Additionally, all extra-marital sexual activity that is physical, constitutes a capital crime.
“Scripture necessitates reserving any and all sexual activity for the marriage relationship. Or to state again, the New Testament conveys – both theologically and exegetically – that all premarital relationships are to be completely non-sexual… Our problem is not that we have failed to recognize the New Testament’s prohibition against premarital sexual activity; rather we have failed to fully reckon with the reality that there is more to sexual activity than intercourse. Oral sex, fondling, and mutual masturbation, for example, are all sexual activities. It is inconceivable that the New Testament’s ethic – insofar as it is an extension of the Torah – intends to leave room for such activities outside of marriage. Once we embrace the biblical ideal that sexual activity must be reserved for the marriage relationship, the question, ‘How far is too far?’ – a perennially vexing question for singles – is easily answered. If an activity is sexual, it is to be reserved for the marriage relationship.” – Gerald Hiestand (“Biblical-Theological Approach To Premarital Sexual Ethics: Or, What Would Paul Say About Making Out,” Bulletin of Ecclesiastical Theology)
“Sex outside of marriage is never moral. This includes all forms of intimate sexual stimulation that stir up sexual passion between unmarried partners.” – The Colorado Statement On Biblical Sexual Morality
 The designation, physical is necessary to distinguish such activity from that which is only mental or “in the heart” (Mat 5:27). Like murder, sexual crimes which are capital in nature relate only to those that involve physical activity.