Judges 2:11 Then the children of Israel did evil in the sight of the Lord, and served the Baals; 12 and they forsook the Lord God of their fathers, who had brought them out of the land of Egypt; and they followed other gods from among the gods of the people who were all around them, and they bowed down to them; and they provoked the Lord to anger. (NKJV)
Here is something we see so often in the Old Testament - of how the children of Israel did evil in serving another God. This is the direct result of not killing off everything that was not of the covenant and allowing squatters in the land.
It becomes clear that God wanted so badly to keep one stock, the line of Abraham, from total perversion for the coming of the Messiah when time was ripe. Without God being in them and being led by the Spirit of the Lord (Romans 8:14), His direct presence here on the Earth as in the New Covenant, Man's propensity to destroy himself and the World through sin were almost guaranteed: see Genesis 6:5 , Genesis 11:5-9 , Genesis 18:20-21 , Isaiah 53:6 ).
Christians who do not pursue the Spirit-led life will often preach about laws and boundaries - we can/cannot do this, we are allowed/not allowed to do that, we must/must not behave in a certain way. These are always needed only in the absence of understanding of the Holy Spirit’s guidance. Like children, as we grow in the Lord we increasingly enjoy freedom in Him to make good decisions outside of just rules. Not so much that we should go ahead to sin, but that we know well enough what is good for us (from knowing the Father’s heart) and to stay with the things that keep us free.
That having been said, there are certain things that harm us more than others, that unless we are well on our way in renewal, would harm us and take us down. An example of this is 1 Corinthians 6:18 where Paul says unequivocally to FLEE sexual immorality, knowing how dangerous it is to us in bringing us back under bondage. Another example is Acts 15:20 . Apart from these, the New Testament church has precious few do's and don'ts.
Paul put it this way to the Galatians:
Galatians 5:16 I say then: Walk in the Spirit, and you shall not fulfill the lust of the flesh. (NKJV)
