Ultimately, the Bible says, the devil is the source of all temptation; he is called "the tempter" in Matthew 4:3. But he is only able to succeed because we let him- and we let him succeed because of our own weakness.
This is one reason why we need Christ. Only He can forgive us when we sin, and only when He can give us strength, by the power of His Spirit, to resist temptation. And in His encounter with the devil at the beginning of His ministry He pointed the way to victory: Using the truth of God's Word to counteract Satan lies.
" Jesus said to him,"Away from me,Satan! For it is written:' Worship the Lord your God, and serve him only." Then the devil left him." -Matthew 4:10-11