Struggling against the Flesh

The flesh is the undead old self that desires the evil pleasures of this world; and even after being brought to life by the power of God, the old self lingers on reaching out for ungodly pleasures. Every day is a struggle against the flesh holding it back and little by little driving it back.

Galatians 5:16-17
So I say, walk by the Spirit, and you will not gratify the desires of the flesh. For the flesh desires what is contrary to the Spirit, and the Spirit what is contrary to the flesh. They are in conflict with each other, so that you are not to do whatever you want.