You cannot make your children love the Bible, I allow. None but the Holy Ghost can give us a heart to delight in the Word. But you can make your children acquainted with the Bible; and be sure they cannot be acquainted with that blessed book too soon, or too well.
A thorough knowledge of the Bible is the foundation of all clear views of religion. He that is well-grounded in it will not generally be found a waverer, and carried about by every wind of new doctrine. Any system of training which does not make a knowledge of Scripture the first thing is unsafe and unsound.
You have need to be careful on this point just now, for the devil is abroad, and error abounds. Some are to be found amongst us who give the Church the honour due to Jesus Christ. Some are to be found who make the sacraments saviours and passports to eternal life. And some are to be found in like manner who honour a catechism more than the Bible, or fill the minds of their children with miserable little story-books, instead of the Scripture of truth. But if you love your children, let the simple Bible be everything in the training of their souls; and let all other books go down and take the second place.
Care not so much for their being mighty in the catechism, as for their being mighty in the Scriptures. This is the training, believe me, that God will honour. The Psalmist says of Him, " Thou hast magnified Thy Word above all Thy name" (Ps. cxxxviii. 2); and I think that He gives an especial blessing to all who try to magnify it among men.
See that your children read the Bible reverently. Train them to look on it, not as the word of men, but as it is in truth, the Word of God, written by the Holy Ghost Himself, all true, all profitable, and able to make us wise unto salvation, through faith which is in Christ Jesus.
See that they read it regularly. Train them to regard it as their soul's daily food, as a thing essential to their soul's daily health. I know well you can not make this anything more than a form; but there is no telling the amount of sin which a mere form may indirectly restrain.
See that they read it all. You need not shrink from bringing any doctrine before them. You need not fancy that the leading doctrines of Christianity are things which children cannot understand. Children understand far more of the Bible than we are apt to suppose.
Tell them of sin, its guilt, its consequences, its power, its vileness: you will find they can comprehend something of this.
Tell them of the Lord Jesus Christ, and His work for our salvation, the atonement, the cross, the blood, the sacrifice, the intercession: you will discover there is something not beyond them in all this.
Tell them of the work of the Holy Spirit in man's heart, how He changes, and renews, and sanctifies, and purifies: you will soon see they can go along with you in some measure in this. In short, I suspect we have no idea how much a little child can take in of the length and breadth of the glorious gospel. They see far more of these things than we suppose.
As to the age when the religious instruction of a child should begin, no general rule can be laid down. The mind seems to open in some children much more quickly than in others. We seldom begin too early. There are wonderful examples on record of what a child can attain to, even at three years old.
Fill their minds with Scripture. Let the Word dwell in them richly. Give them the Bible, the whole Bible, even while they are young.
Note: We love Scripture songs. Bible Truth Music offers "Bible Songs For Kids" Vol. 1-3. They are of course KJV. And the music is actually fun and easy to listen to. Each CD has 25 Scripture songs on various topics. They can be downloaded for about $10. Our kids love them. We use Scripture songs to help the whole family memorize God's Word. Jocelyn, our three-year-old has only been able to memorize part of Heb. 11:6 by rote after two weeks, but when we put it to song she learned the whole thing. She still has trouble saying it, but she can sing it! Our two-year-old, Kaylee, even joins in when we sing. Our almost five-year-old, Jerry, has memorized it and can recite it without even pausing. I'm amazed how many Scripture songs the kids learn. They will stay with them forever. Just a thought.
God bless. Keep on a prayin'!