By Luke Lancaster
Many denominations are convinced that heaven is guaranteed for Christians. They think that once a Christian is saved, then he is always saved. This is totally false, for the Bible teaches the notion of mortal sin. Christians can lose their salvation, and in particular, through the mortal sin of hatred. This sin is tied in with unforgiveness, which also is a mortal sin, and can result in somebody going to hell.
The Catechism says, “Hatred of the neighbor is a grave sin when one deliberately desires him grave harm” (CCC, para. 2303). This is because it is so deeply opposed to charity. Christians have Christ's love in their hearts, and to hate another person would result in him or her being cut off from Christ (John 15:6).
St. Paul said, "it is no longer I who live, but Christ who lives in me" (Gal. 2:20). Christ’s eternal life flows through the veins of Christians, and He hated no one. If Christians hate somebody, then that life ceases in the Christian until he repents. Scripture says, “Any one who hates his brother is a murderer, and you know that no murderer has eternal life abiding in him” (1 Jn. 3:15). Christ's eternal life in the believer is supposed to overflow into heaven, however, if the believer hates his brother, then he has fallen from grace.
Christians need to pray for the grace of love and forgiveness in their lives daily. For mortal sin is a possibility. To hate another person will cause the Christian to go to hell. Christians need to look at whoever they hate with the love of Christ, knowing that whatever they do to the least of Christ's brethren, they do unto him (Matthew 25:45).