Matthew 18:3

and said: "I solemnly say to you, unless you turn and become like little children, you can never get into the kingdom of heaven at all.

Mark 10:14-15

When Jesus saw it, He was indignant, and said to them, "Let the little children come to me, and stop keeping them from it, for to such as these the kingdom of God belongs.

1 Peter 2:2

and like new-born babies thirst for pure spiritual milk, so that by it you may grow up to final salvation,

1 Corinthians 14:20

Brothers, stop being children in intelligence, but as to evil keep on being babies; and yet as to intelligence be men of maturity.

Matthew 19:14

But Jesus said, "Let the little children alone, and stop preventing them from coming to me, for to such as these the kingdom of heaven belongs."

Matthew 5:20

For I tell you that unless your righteousness far surpasses that of the scribes and Pharisees, you will never get into the kingdom of heaven at all.

Luke 18:16-17

But Jesus called them to Him and said, "Let the little children come to me, and stop preventing them from it, for to such as these the kingdom of God belongs.

Luke 22:32

but I have prayed especially for you that your own faith may not utterly fail. And you yourself, after you have turned, must strengthen your brothers."

Matthew 5:18

I have not come to set them aside but to fill them up to the brim. For I solemnly say to you, heaven and earth would sooner pass away than the dotting of an 'i' or the crossing of a 't' from the law, until it all becomes in force.

Matthew 6:2

So whenever you do your deeds of charity, never blow your own horn in public, as the hypocrites are in the habit of doing in the synagogues and on the street corners, to be praised by the people. I solemnly say to you, they already have their reward.

Matthew 6:5

"Also, whenever you pray, you must not be like the hypocrites, for they love to pray standing in the synagogues and on the street corners, to attract the attention of people. I solemnly say to you, they already have their reward.

Matthew 6:16

"Also whenever you fast, you must not look gloomy like the hypocrites, for they put on a gloomy countenance, to let people see them fasting. I solemnly say to you, they already have their reward.

Matthew 13:15

For this people's soul has grown dull, and with their ears they can scarcely hear, and they have shut tight their eyes, so that they will never see with their eyes, and hear with their ears, and understand with their hearts, and turn to me, so that I may cure them!'

Matthew 19:23

Jesus said to His disciples, "I solemnly say to you, it will be hard for a rich man to get into the kingdom of heaven.

Mark 4:12

'They may look and look and yet not see, And listen and listen and yet not understand, Lest, perchance, they should turn and be forgiven.'"

Luke 13:24

"You must struggle on to get in through the narrow door, for I tell you, many will try to get in, but will not succeed,

John 1:51

Then He said to him, "I most solemnly say to you all, you will see heaven opened and the angels of God going up, and coming down upon the Son of Man!"

John 3:3

Jesus answered him, "I most solemnly say to you, no one can ever see the kingdom of God, unless he is born from above."

John 3:5

Jesus answered, "I most solemnly say to you, no one can ever get into the kingdom of God, unless he is born of water and the Spirit.

Acts 3:19

So now repent and turn to Him, to have your sins wiped out, that times of revival may come from the presence of the Lord,

Acts 14:22

strengthening the hearts of the disciples and encouraging them to continue in the faith, and warning them that it is through enduring many hardships that we must get into the kingdom of God.

Acts 28:27

For this people's soul has grown dull, and they scarcely hear with their ears, and they have shut tight their eyes, so that they may never see with their eyes, and understand with their souls, and turn to me, that I may cure them."'

James 5:19-20

My brothers, if any one of you has wandered away from the truth, and someone brings him back,

2 Peter 1:11

for it is in this way that to you will be generously granted a triumphant admittance into the eternal kingdom of our Lord and Saviour Jesus Christ.

Treasury of Scripture Knowledge

Summary

And said, Verily I say unto you, Except ye be converted, and become as little children, ye shall not enter into the kingdom of heaven.

Bible References

And become

Mark 10:14
When Jesus saw it, He was indignant, and said to them, "Let the little children come to me, and stop keeping them from it, for to such as these the kingdom of God belongs.
Luke 18:16
But Jesus called them to Him and said, "Let the little children come to me, and stop preventing them from it, for to such as these the kingdom of God belongs.
1 Corinthians 14:20
Brothers, stop being children in intelligence, but as to evil keep on being babies; and yet as to intelligence be men of maturity.
1 Peter 2:2
and like new-born babies thirst for pure spiritual milk, so that by it you may grow up to final salvation,

General references

Mark 10:15
I solemnly say to you, whoever does not accept the kingdom of God as a little child does, will never get into it at all."
Luke 9:46
Now a controversy sprang up among them as to which of them might be the greatest.
Luke 22:26
But you are not to do so. On the contrary, the greatest among you must be like the youngest and the leader as the servant.
Acts 8:19
and said, "Give me this power too, that when I lay my hands on anyone he may receive the Holy Spirit."