Generally children cannot really grasp the concept of salvation until they are in their teens. What is necessary is that they should be made familiar with the scriptures from an early age. This will give them a foundation on which faith can be built. It is a knowledge of the scriptures that is able to make them ‘wise unto salvation’.
2 Timothy 3:15 And that from a child thou hast known the holy scriptures, which are able to make thee wise unto salvation through faith which is in Christ Jesus.
They should be brought up in the ‘nurture and admonition of the Lord’ so that they have a sound basis for morality.
Ephesians 6:4 And, ye fathers, provoke not your children to wrath: but bring them up in the nurture and admonition of the Lord.
In teaching children the commandments of Christ, the principle of the instruction given through Moses should be followed:
Deuteronomy 11:19 And ye shall teach them unto your children, speaking of them when thou sittest in thy house, and when thou goest on the way, and when thou liest down, and when thou risest up;
When they are old enough to read they should be included in the family daily Bible reading. The family daily Bible reading should follow a plan which repeatedly covers the whole of the Bible. In this way they will have the benefit of the repetition of the ‘whole counsel of God’.
2 Timothy 3:16 All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness: 17 That the man of God may be perfect, throughly furnished unto all good works.
Faith or belief can come only from the scriptures.
Romans 10:17 So then faith cometh by hearing, and hearing by the word of God.
I hope you have found this helpful.
God bless you,