Todd Friel of Wretched Radio does an excellent job on his radio show. The following is a clip of him witnessing on the campus of Georgia Tech.
Todd is correct that the purpose of life has to do with God’s attributes. I use this idea to counter the objection that eternal punishment is unjust. The greatest commandment is the purpose of life: to love God (Matthew 22:37) Those who love God go to be with Him in heaven (John 14:23). In addition, since the penalty for sin has been paid by Jesus (1 Peter 2:24), they are not punished themselves (Romans 8:1). Those who don’t love God must be separated to a place reserved for people who don’t love Him (Revelation 20:15). In addition, since they did not receive a pardon for their sins, they themselves must pay the penalty (2 Peter 2:4).
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