Mark 7 states:
[Mar 7:15, 20-23 NASB] 15 there is nothing outside the man which can defile him if it goes into him; but the things which proceed out of the man are what defile the man. ... 20 And He was saying, "That which proceeds out of the man, that is what defiles the man. 21 "For from within, out of the heart of men, proceed the evil thoughts, fornication, thefts, murders, adulteries, 22 deeds of coveting and wickedness, as well as deceit, sensuality, envy, slander, pride and foolishness. 23 "All these evil things proceed from within and defile the man."
If all these things come from within a man, why is a being called "Satan" blamed for evil? What is left for him to do? Also:
[Jas 1:13-15 KJV] 13 Let no man say when he is tempted, I am tempted of God: for God cannot be tempted with evil, neither tempt he any man: 14 But every man is tempted, when he is drawn away of his own lust, and enticed. 15 Then when lust hath conceived, it bringth forth sin: and sin, when it is finished, bringth forth death.
Do we only have ourselves to blame?