Because God is love, He's a forgiving God. It's like if you cheat on your partner, you say you're sorry and you really mean it, and you promise never to do it again. Then, if you're lucky, your partner will forgive you. It's like that with God, but you're always lucky in that if you ask, with sincerity from your heart, He always forgives and then you are safe. All pretty simple really.

A Biblical reference is found in Exodus 20:20, which says that fearing God keeps us from sinning. Logic tells us that God cannot love evil, because evil is the opposite of love. God loves, but He doesn't love everything. God loves the sinner, but not the sin, and He gets pretty peeved when we sin. If we die as a sinner, we go to Hell, and I reckon that's where most souls go. Hell, whatever that is, and God's anger, sound like things to REALLY fear!