The way to come to God!
Note the expression in verse 15. If a person is going to be saved, that is become a Christian, they need to submit to God's authority (receive the kingdom of God) as a little child.
This means we come dependant upon God, trusting Him, respecting and loving Him and recognising that God is wise, strong, caring and has our best interests in His heart.
Salvation is of the Lord. Faith is in God. Grace comes from God. Our part is to turn to God confessing our sin and resting on Jesus Christ for salvation.
Will you come to God as a child or are you too grown up to trust Him for your eternal destiny.
And they brought young children to him, that he should touch them: and his disciples rebuked those that brought them.
But when Jesus saw it, he was much displeased, and said unto them, Suffer the little children to come unto me, and forbid them not: for of such is the kingdom of God.
Verily I say unto you, Whosoever shall not receive the kingdom of God as a little child, he shall not enter therein.
And he took them up in his arms, put his hands upon them, and blessed them.
And when he was gone forth into the way, there came one running, and kneeled to him, and asked him, Good Master, what shall I do that I may inherit eternal life?
And Jesus said unto him, Why callest thou me good? there is none good but one, that is, God.
Thou knowest the commandments, Do not commit adultery, Do not kill, Do not steal, Do not bear false witness, Defraud not, Honour thy father and mother.
And he answered and said unto him, Master, all these have I observed from my youth.
Then Jesus beholding him loved him, and said unto him, One thing thou lackest: go thy way, sell whatsoever thou hast, and give to the poor, and thou shalt have treasure in heaven: and come, take up the cross, and follow me.
And he was sad at that saying, and went away grieved: for he had great possessions.
And Jesus looked round about, and saith unto his disciples, How hardly shall they that have riches enter into the kingdom of God!
And the disciples were astonished at his words. But Jesus answereth again, and saith unto them, Children, how hard is it for them that trust in riches to enter into the kingdom of God!
It is easier for a camel to go through the eye of a needle, than for a rich man to enter into the kingdom of God.
And they were astonished out of measure, saying among themselves, Who then can be saved?
And Jesus looking upon them saith, With men it is impossible, but not with God: for with God all things are possible.
Then Peter began to say unto him, Lo, we have left all, and have followed thee.
And Jesus answered and said, Verily I say unto you, There is no man that hath left house, or brethren, or sisters, or father, or mother, or wife, or children, or lands, for my sake, and the gospel's,
But he shall receive an hundredfold now in this time, houses, and brethren, and sisters, and mothers, and children, and lands, with persecutions; and in the world to come eternal life.
But many that are first shall be last; and the last first.