Proverbs 7:25
Solomon warns us of allowing our hearts to lower its standards to that of sin. In the following verses, he describes the woes of when the sin has matured in our heart. Quite a dreadful picture of what happens to us internally as well as externally when sin has matured in our life.
I don't think anyone awakes in the morning and boldly states that they intend to commit a horrible sin that day. But just as described in the preceding verses, we are incrementally drawn into the filth of sin, sometimes in a manner in which we are not aware. However, once we start sliding down the slippery slope, it takes extreme effort to extract ourselves! The cost to us is sometimes great and affects all aspects of our life - physical, emotional and spiritual.
How do we prevent such pain? As Solomon states in the first verse of the chapter - My son, keep my words, and lay up my commandments with thee. (Proverbs 7:1) If we keep God's commandments in our heart, there is no room for sin. And our heart never takes the first step down the slippery slope leading to sin.