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There is probably nothing more painful for a Christian parent than to have one of her children rebel against the lord and against her. After you have spent years loving your child, raising him in the Christian way and showing him the path to salvation; after investing so much time and resources, the pain of having that child reject you and your God goes deep. It makes you feel like a failure. It makes you want to question and even doubt God. It fills you with grief that just won’t go away.
But then, what does expect from you at such a time? Should you just fold your hands and allow the devil the liberty too destroy him? On the contrary, He wants you to persevere in prayer and keep loving your child, hoping and believing that God can and will save him and make him a better person in future.
Do children always rebel and go their way because of parental failure? No, not always, although it is generally true that if children are trained up properly in the way of the lord they will naturally follow the lord as they grow into adult, it is not always the case. This is because as children grow up and begin to assume responsibilities, they tend to want to think and decide for themselves. Besides, as they grow and interact with their peers, they get exposures that are capable of influencing their decisions.
Thus, godly parents, who to the best of their abilities, seek to raise their children in the faith, may still have children who turn away. But when this happens, do not apportion blame, do not give up hope, do not stop praying and trusting God and do not stop loving and caring for the child. Like the father in Biblical illustration of the prodigal son, show:
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HEARTFELT COMPASSION. Have compassion for your straying child. Sometimes, he may be in deep need of assistance from you. At such times, at such times, don’t open up his messed-up life in his face and tell him off. It is the time to show him heartfelt compassion as Jesus would do to any sinner who comes to Him for help. Do not hesitate to show him that you care.

AFFECTION. Besides making sure his needs are met, show him physical affection. Show him that you love him in spite of his present lifestyle. Let genuine love be reflected in all your actions towards him.
HUMILITY. This may be very hard for you but don’t be ashamed to identify with your child no matter how far he has deviated. Shut your eyes and ears to the public opinions and reactions. Stick close to him especially at this moments of dejection. Don’t play the ‘holier-than-thou’ card.

UNDESERVED GENEROSITY. Be gracious unto your child. This does not rule out indiscipline. But let there be a noticeable balance between the two. Let him know how gracious God is through your generosity towards him.

UNDESERVED ACCEPTANCE. It is very common with hurting parents to say, “I DISOWN YOU” to their straying children. But this is not what Jesus would say to any of His sheep that goes astray. Rather, He would seek it until He finds it because it is still His sheep. Prayerfully show your straying child undeserved acceptance and by the mercy of God, he will trace his way back to God.
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"The truth is, the answers always comes, no matter how long it takes"