The Book of Genesis tells us early on that every inclination of the thoughts of man were only evil all the time. It is not only the final act that typifies sin, but the process leading up to it, beginning with our hearts. We also learn that salvation is aimed out our hearts, not our bodies alone. It is hatched in evil desire. It also applies to anything that the flesh craves which God has not given.
Sin begins with evil desire.
Every person is haunted by lust. It begins in our soul, which is like a sponge always thirsting for something to fill itself. All of its actings . The will itself is bent toward lust, and sin Adam s Fall, people consult first with their desires. Lust is the seed of sin.