Heaven or hell is determined by whether a person believes (puts their trust) in Christ alone to save them (John 3:16, 36, etc.).
Hell was designed originally for Satan and his demons (Matthew 25:41; Revelation 20:10).
Hell will also punish the sin of those who reject Christ (Matthew 13:41,50; Revelation 20:11-15; 21:8).
Matthew 13:50 “furnace of fire…weeping and gnashing of teeth”
Mark 9:48 “where their worm does not die, and the fire is not quenched”
Revelation 14:10 “he will be tormented with fire and brimstone”
Christian Hell is eternal and irreversible:
Revelation 14:11 “the smoke of their torment goes up forever and ever and they have no rest day and night”
Revelation 20:14 “This is the second death, the lake of fire”
Revelation 20:15 “If anyone’s name was not found written in the book of life, he was thrown into the lake of fire”
According to Christians Hell is NOT too severe a punishment for man’s sin because:
God doesn’t send people to hell, they choose it (Romans 1:18,21,25).
God has provided the way of hell or salvation to all (John 3:16,17; 2 Corinthians 5:14,15; 1 Timothy 2:6; 4:10; Titus 2:11; 2 Peter 3:9).
A person decides to either trust in Christ or else he/she rejects Christ and goes to hell (John 3:16;3:36).
Our sin does merit hell (Romans 1:32; 2:2,5,6).