While "sin" might be a word we commonly know and use, it is often not clear what "sin" is. We tend to make lists of what is sinful and what is not sinful, and those lists might differ from culture to culture, and even sometimes between Christian traditions (e.g. denominations). This short description of what sin is provides the underlying principles rather than to give yet another list.

The word used for "sin" means "to miss the mark". It was a word commonly used when archers used to shoot at a target and not hit it. This meaning therefore provides the basic point of reference from which we look at what sin is. Clearly then, to sin is to miss the purpose for which God has created us, and to live a life that does not follow what He had in mind with humankind. If we take into account that God created us in His image (Gen 1:26-28), then it means that whenever we do not live up to that goal we are sinning.

God loves us, has goodwill towards us, and desires for every human being to thrive. To the extent we participate in this effort, we are advancing His purpose. Whenever we do not do justice to this, we are "missing the mark". We can therefore never define sin outside of a clear understanding of who God is and what His purposes are. God is the life-giver, not working towards or advancing any evil or degradation. To the extent we follow Him in this effort, we are not "missing the mark".

It is sin that kills and destroys (Rom 6:23). Missing the mark means that we participate in and advance that which is not of God. In other words, we are partaking in activities which are not giving life and over time causes us to shrivel up inwardly and experience an inner death and emptiness. It is easy to run after instant gratification and "pleasure" of which the impact on our lives is not good and upbuilding. This is one way in which we "miss the mark".

So what is sexual sin? According to the Bible it is all sexual activity outside of a marriage, as well as degrading, abusive and exploitative sexual practices even within a marriage. God created sex to portray the union we have with Him (read about is in 1 Cor 6), and therefore we need to treat sex as that very special activity that unites a husband and a wife, just like we are spiritually united with Him when we believe in Him.

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