What will happen to members of non-Christian faiths?
If the Word of God is true, Christianity is the only way to achieve eternal life. Accepting Jesus as your personal savior is the only way to obtain salvation. It may not be politically correct to say this, but if Jesus is truly the Son of God, then neither Islam, Buddhism, Hinduism, nor any other faith can redeem your eternal soul.
In John 14:6, Jesus made it very clear that He is the only mediator who can span the sin-rift that exists between God and man: "I am the way, the truth, and the life: no man cometh unto the Father, but by me."