As Wesleyans we believe that a true Christian can veer off of the Road of Faith, i.e. can apostatize and become unsaved once again. It's not a comfortable doctrine; I wish I could believe in eternal security. However, both the Scriptures and life experiences have taught me that once in grace does not automatically mean always in grace.
In his Sermons on Several Occasions, # 19, "The Great Privilege of those that are Born of God", John Wesley expounds on the text of 1 John 3.9a, "Whosoever is born of God doth not commit sin"; in this passage he describes how a believer can fall into sin:
You see the unquestionable progress from grace to sin: Thus it goes on, from step to step. (1.) The divine seed of loving, conquering faith, remains in him that is born of God. 'He keepeth himself,' by the grace of God, and 'cannot commit sin.' (2.) A temptation arises; whether from the world, the flesh, or the devil, it matters not. (3.) The Spirit of God gives him warning that sin is near, and bids him more abundantly watch unto prayer. (4.) He gives way, in some degree, to the temptation, which now begins to grow pleasing to him. (5.) The Holy Spirit is grieved; his faith is weakened; and his love of God grows cold. (6.) The Spirit reproves him more sharply, and saith, 'This is the way; walk thou in it.' (7.) He turns away from the painful voice of God, and listens to the pleasing voice of the tempter. (8.) Evil desire begins and spreads in his soul, till faith and love vanish away: He is then capable of committing outward sin, the power of the Lord being departed from him.This is a disastrous situation!
Wesley likens the Christian life as an action/reaction relationship toward God. God breathes life by the Spirit and the soul of the believer reacts in, "an unceasing return of love, praise, and prayer, offering up all the thoughts of our hearts, all the words of our tongues, all the works of our hands, all our body, soul, and spirit, to be a holy sacrifice, acceptable unto God in Christ Jesus."
What if it doesn't happen? What if a soul grows cold toward God?
For it plainly appears, God does not continue to act upon the soul, unless the soul re-acts upon God. He prevents us indeed with the blessings of his goodness. He first loves us, and manifests himself unto us. While we are yet afar off, he calls us to himself, and shines upon our hearts. But if we do not then love him who first loved us; if we will not hearken to his voice; if we turn our eye away from him, and will not attend to the light which he pours upon us; his Spirit will not always strive: He will gradually withdraw, and leave us to the darkness of our own hearts. He will not continue to breathe into our soul, unless our soul breathes toward him again; unless our love, and prayer, and thanksgiving return to him, a sacrifice wherewith he is well pleased.Call it what you will: apostasy, losing salvation, forfeiting salvation, backsliding, etc. Yes, Wesleyans uphold that a regenerate Christian can relapse into an unsaved, unregenerate state. The Saint becomes the Sinner.
What is the proper response to this sobering realization? Wesley again has advice for us at the close of her sermon:
Let us learn, Lastly, to follow that direction of the great Apostle, 'Be not high-minded, but fear.' Let us fear sin, more than death or hell. Let us have a jealous (though not painful) fear, lest we should lean to our own deceitful hearts. 'Let him that standeth take heed lest he fall.' Even he who now standeth fast in the grace of God, in the faith that overcometh the world, may nevertheless fall into inward sin, and thereby 'make shipwreck of his faith.' And how easily then will outward sin regain its dominion over him! Thou, therefore, O man of God! watch always; that thou mayest always hear the voice of God! Watch, that thou mayest pray without ceasing, at all times, and in all places, pouring out thy heart before him! So shalt thou always believe, and always love, and never commit sin.Amen.