Our children must learn that they can receive Christ and His salvation only through faith. As John 3:36 says, "He that believeth on the Son hath everlasting life: and he that believeth not the Son shall not see life; but the wrath of God abideth on him."
Thomas Chalmers was having trouble explaining faith to a woman. Somewhat frustrated, he finally left her by exiting through her backyard. He came to a little bridge over a river. When he came to the bridge, he looked at it, touched one side of it, but then jumped back because he was reluctant to put his full weight on it. The woman watched him, thinking his behavior strange. But Chalmers continued his strange way of approaching the bridge, then jumping back. Finally the woman shouted from her back porch: "Go ahead. Lean your all on the bridge."
Chalmers then shouted back, "And you, ma'am, should lean your all on the Lord Jesus Christ!"
That is what faith does—it leans on the Savior. The believer throws all his weight on Christ, trusting Him fully for salvation and forgiveness of sin.
This excerpt is taken from Parenting By God's Promises by Joel Beeke.