Is physical intimacy outside of marriage wrong?
With Physical intimacy between a Man and Woman a little physical touch can very quickly lead to more. If you didn't want to light a fire you wouldn't strike a match. So it is with physical intimacy - touching and kissing naturally lead to sex. If you want to obey God's word you should not try to push your behaviour as close to breaking God's commands as possible before drawing the line. It would be much safer to draw the line earlier and have a healthy regard for the danger involved. So you may feel that kissing and touching are not appropriate if you are simply dating.
Throughout the Bible the Holy Spirit reveals that God has designed physical intimacy between Man and Woman to be enjoyed within the safety of marriage. The exclusive relationship of one man and one woman for life creates a new family unit (see Genesis 2:24). It is the basic building block of society and is protected twice in the Ten Commandments. In Exodus 20:14 "You shall not commit adultery". And in Exodus 20:17 "You shall not covet your neighbour's wife".
In short Marriage is the only appropriate relationship to enjoy physical intimacy between man and woman - it is God's good gift to us for our benefit. Going any way other than God's original intention will only lead to frustration, anger, hurt, pain, broken relationships and shame. That is always the consequence of sin, however appealing or attractive it looks at first, because God will judge all sin including sin in our relationships.
"Marriage should be honoured by all, and the marriage bed kept pure, for God will judge the adulterer and all the sexually immoral." Hebrews 13:4 (NIV)
When Jesus came - he continued to uphold marriage as a God given institution. And he put his finger on why so many of the people of the day were getting divorced and remarrying. Jesus taught that they were not loving but lustful (wanting to have their own desires met). He pointed the finger towards people's hearts. He explained that even looking at a person you are not married to with lustful desire (wanting them for yourself) is the same as committing adultery. See below:
“You have heard that it was said, 'Do not commit adultery.' But I tell you that anyone who looks at a woman lustfully has already committed adultery with her in his heart. If your right eye causes you to sin, gouge it out and throw it away. It is better for you to lose one part of your body than for your whole body to be thrown into hell. And if your right hand causes you to sin, cut it off and throw it away. It is better for you to lose one part of your body than for your whole body to go into hell.” Matthew 5:27-29 (NIV)
What Jesus’ teaching on the Sermon on the Mount shows us is that God is not interested in us just keeping the rules. Instead He is looking for hearts that are turned towards Him and share His attitudes and desires.
The Bible makes it clear that lust is not love and does not please God. If you want to be physically intimate with a person because you have chosen to love them then you will readily commit to marriage because you will want to share the rest of your life with them. For a man it would mean that you are seeking to give yourself up for them as Christ loved the church (see Ephesians 5:25,32) and for a woman that you are willing to submit to them as to God (see Ephesians 5:22).
If, however, you want what you can get from a temporary partner or are seeking to take pleasure from someone you desire - then that is lust. See below:
"What causes fights and quarrels among you? Don't they come from your desires that battle within you? You want something but don't get it. You kill and covet, but you cannot have what you want. You quarrel and fight. You do not have, because you do not ask God. When you ask, you do not receive, because you ask with wrong motives, that you may spend what you get on your pleasures." James 4:1-4 (NIV)
If you do think that you are acting in lust then be careful to identify your behaviour as wrong and make a conscious decision to repent (turn from it).
If you give in to your sinful desires they will lead you away from the Lord and the life He offers. As it says in James 1:14-15:
"each one is tempted when, by his own evil desire, he is dragged away and enticed. Then, after desire has conceived, it gives birth to sin; and sin, when it is full-grown, gives birth to death." (NIV)
So please choose what is right - turn from sin and decide to go God's way - godliness with contentment is great gain! (1 Timothy 6:6). Going God's way and waiting for God to provide good gifts in His perfect timing is always a better path to take than decisions based on sinful desires.