"Why are there so many different religions?"

It has been well said that "religion" is man’s way of trying to deal with his guilt. Different religions have different ways of attempting to rid their adherents of sin and its consequences. They fast, pray, deny themselves legitimate pleasures, or chasten themselves, often to a point of inflicting pain. They do this because they have a concept of what they think God (or "the gods") is like, so they seek to establish their own righteousness, being "ignorant of God’s righteousness." The Good News of the Christian faith is that no one need suffer the pains of religious works. Christ’s blood can cleanse our conscience from the "dead works" of religion (Hebrews 9:14). Jesus took our punishment upon Himself, and He is the only One who can save us from sin and death. See Acts 4:12 and John 14:6.