One of the terms often used of believers who have fallen away from Christ is backslider. Though the word backslider is not found in the New Testament, the concept is still taught. A backslider is a Christian, who has fallen into sin and out of fellowship with God. It is important to note that the backslider is still a Christian. It is not a believer who has lost his salvation. Salvation is a free gift from God and cannot be lost once the gift has been received.

Loss

His condition is similar to the prodigal son (Luke 15). He has fallen out of fellowship with God and gone to the world to find fulfillment. Any pleasures enjoyed are only temporary. When a person backslides or falls away from the Lord they will lose their fellowship with God, not their salvation.

Corinthian Church

The New Testament provides us with an account of the backsliding of some members of the Corinthian church. Their sins were of such a nature that God sent sickness and death to some of them. They were backslidden and had died while in that state. And yet they went to heaven:

For this reason many are weak and sick among you, and many sleep. For if we would judge ourselves, we would not be judged. But when we are judged, we are chastened by the Lord, that we may not be condemned with the world (1 Corinthians 11:30-32).

Disciplined

The word apostasy means falling away. The Bible uses the term apostate to describe one who has turned their back on Christ and the gospel. It is not the same as backsliding. A backslider is a believer who falls into sin and out of fellowship with God. An apostate was never a true believer. Though an apostate may sound like a believer for a time, they eventually will depart from other believers. The Apostle John wrote:

Little children, it is the last hour; and as you have heard that the Antichrist is coming, even now many antichrists have come, by which we know that this is the last hour. They went out from us, but they were not of us; for if they had been of us, they would have continued with us; but they went out that they might be made manifest, that none of them were of us (1 John 2:18,19).

The apostate denies the fundamentals of the faith. The apostate does not lose their salvation, they were never saved in the first place.

Judas

A perfect example of an apostate is Judas Iscariot. Although he was one of the inner circle of Jesus' disciples he was never a true believer. This was demonstrated by his betrayal of Jesus for 30 pieces of silver.

Not The Same

An apostate is not the same as a backslider. An apostate is one who has departed from the faith. A backslider will eventually return to the Lord because he cannot live happily in sin.

Have No Dealings

We are told to have no dealings with apostates.

Whoever transgresses and does not abide in the doctrine of Christ does not have God. The one who abides in the doctrine of Christ has both the Father and the Son. If anyone comes to you and does not bring this doctrine, do not receive them into your house (2 John 9-11).

Summary

Though a person may profess faith in Christ their actions will determine if they truly know Him. Unbelievers who mingle with Christians for a time will eventually be found out.