Sin can be described in a variety of ways, but the common theme is falling short of God’s standard (Rom. 6.23). Sin is universal, both inherited through Adam (Rom. 5.12) and committed by each person, individually (Ps. 14.1, 3; Eph. 2.3; 1 Jn. 1.8-10). Because of man’s corrupted nature, we each have “flesh” that leads us toward sin and away from doing God’s will (Rom. 7.18; Gal. 5.16-24). While the devil may tempt, much of our sin problem arises from corrupt desires within us (James 1.14-15). Some desires are God-given and good, but we have a way of taking legitimate needs (enjoying things – Creation; obtaining things – stewardship; do things/achieve) and twisting them into “the lust of the flesh, lust of the eyes, and the pride of life” (1 Jn. 2.16).
Jesus also said “the world” hated Him and would hate us (Jn. 7.7). The world is a kind of impersonal spiritual force, or system, that is set against God (Jn. 14.17) and believers are to be set against it (James 4.4) by being salt and light within it (Mt. 5.16).