People can fall from faith. The Bible warns, "If you think you are standing firm, be careful that you don't fall" (! Corinthians 10:12). Some among the Galatians had believed for a while, but had fallen into soul-destroying error. Paul warned them, "You who are trying to be justified by law have been alienated from Christ; you have fallen away from grace" (Galatians 5:4). In his explanation of the parable of the sower, Jesus says, "Those on the rock are the ones who receive the word with joy when they hear it, but they have no root. They believe for a while, but in time of testing they fall away" (Luke 8:13). According to Jesus a person can believe for a while and then fall away. While they believed they possessed eternal salvation, but when they fell from faith they lost God's gracious gift.
Those who have fallen from faith must be reconverted if they are going to be saved. As Christians we will want to call those who have fallen to repentance (sorrow for sin and trust in Jesus for forgiveness). St. Paul writes, "Brothers, if someone is caught in a sin, you who are spiritual should restore him gently. But watch yourself, or you also may be tempted (Galatains 6:1).
The purpose of church discipline is to bring people to repentance. Jesus instructs, "If your brother sins against you, go and show him his fault just between the two of you. If he listens to you, you have won your brother over. But if he will not listen, take one or two others along, so that 'every matter may be established by the testimony of two or three witnesses.' If he refuses to listen to them, tell it to the church; and if he refuses to listen even to the church, treat him as you would a pagan or a tax collector. I tell you the truth, whatever you bind on earth will be bound in heaven, and whatever you loose on earth will be loosed in heaven" (Matthew 18:15-18).
The Lord sent Nathan the prophet to call King David to repentance after his double sin of adultery with Bathsheba and the murder of her husband Uriah (2 Samuel 12:1-23). Jesus brought Peter to repentance with a look that recalled his warning that Peter would deny him and Peter's vain boast that he would never deny him or forsake Jesus (Mathhew 26:69-75).
Christian love demands that we call sinners to repentance lest they turn their backs on their Savior and be lost forever.
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