Today may be the evil day which the malignantly evil one will attack your faithful mind resting in Christ, and it may not be. The evil day is the only day you must take up the shield of faith with which to extinguish the flaming arrows of the evil one. The sin nature is always inside you, and doesn’t give the same lusts as the evil one into your mind.
The sin nature is the source of most of the lusts which cross your mind. The works of the flesh are found in Galatians 5:19-21. These are not overcome with the full armor of God, but by submitting to the Holy Spirit and denying the beginning of a series of thoughts in the mind.