Matthew 18:3

"I tell you, unless you change and become like little children, you will not enter the Kingdom of Heaven at all.

Mark 10:14-15

When, however, Jesus saw this, he was indignant. "Let the little children come to me," he said, "do not hinder them; for it is to the childlike that the Kingdom of God belongs.

1 Peter 2:2

like newly born infants, crave pure spiritual milk, so that you may be enabled by it to grow till you attain Salvation--

1 Corinthians 14:20

Brothers, do not show yourselves children in understanding. In wickedness be infants, but in understanding show yourselves men.

Matthew 19:14

Jesus, however, said: "Let the little children come to me, and do not hinder them, for it is to the childlike that the Kingdom of Heaven belongs."

Matthew 5:20

Indeed I tell you that, unless your religion is above that of the Teachers of the Law, and Pharisees, you will never enter the Kingdom of Heaven.

Luke 18:16-17

Jesus, however, called the little children to him. "Let the little children come to me," he said, "and do not hinder them; for it is to the childlike that the Kingdom of God belongs.

Luke 22:32

But I prayed for you, Simon, that your faith should not fail. And you, when you have returned to me, are to strengthen your Brothers."

Matthew 5:18

For I tell you, until the heavens and the earth disappear, not even the smallest letter, nor one stroke of a letter, shall disappear from the Law until all is done.

Matthew 6:2

Therefore, when you do acts of charity, do not have a trumpet blown in front of you, as hypocrites do in the Synagogues and in the streets, that they may be praised by others. There, I tell you, is their reward!

Matthew 6:5

And, when you pray, you are not to behave as hypocrites do. They like to pray standing in the Synagogues and at the corners of the streets, that they may be seen by men. There, I tell you, is their reward!

Matthew 6:16

And, when you fast, do not put on gloomy looks, as hypocrites do who disfigure their faces that they may be seen by men to be fasting. That, I tell you, is their reward!

Matthew 13:15

For the mind of this nation has grown dense, And their ears are dull of hearing, Their eyes also have they closed; Lest some day they should perceive with their eyes, And with their ears they should hear, And in their mind they should understand, and should turn--And I should heal them.'

Matthew 19:23

At this, Jesus said to his disciples: "I tell you that a rich man will find it hard to enter the Kingdom of Heaven!

Mark 4:12

'Though they have eyes, they may see without perceiving; And though they have ears, they may hear without understanding; Lest some day they should turn and be forgiven.'

Luke 13:24

"Strive to go in by the small door. Many, I tell you, will seek to go in, but they will not be able,

John 1:51

In truth I tell you," he added, "you shall all see Heaven open, and 'the angels of God ascending and descending' upon the Son of Man."

John 3:3

"In truth I tell you," exclaimed Jesus, "unless a man is reborn, he cannot see the Kingdom of God."

John 3:5

"In truth I tell you," answered Jesus, "unless a man owes his birth to Water and Spirit, he cannot enter the Kingdom of God.

Acts 3:19

Therefore, repent and turn, that your sins may be wiped away; so that happier times may come from the Lord himself,

Acts 14:22

Reassuring the minds of the disciples, urging them to remain true to the Faith, and showing that it is only through many troubles that we can enter the Kingdom of God.

Acts 28:27

For the mind of this nation has grown dense, and their ears are dull of hearing, their eyes also have they closed; lest some day they should see with their eyes, and with their ears they should hear, and in their mind they should understand, and should turn--and I should heal them.'

James 5:19-20

My Brothers, should one of you be led astray from the Truth, and some one bring him back again,

2 Peter 1:11

For thus you will be given a triumphant admission into the eternal Kingdom of our Lord and Savior, 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, however, Jesus saw this, he was indignant. "Let the little children come to me," he said, "do not hinder them; for it is to the childlike that the Kingdom of God belongs.
Luke 18:16
Jesus, however, called the little children to him. "Let the little children come to me," he said, "and do not hinder them; for it is to the childlike that the Kingdom of God belongs.
1 Corinthians 14:20
Brothers, do not show yourselves children in understanding. In wickedness be infants, but in understanding show yourselves men.
1 Peter 2:2
like newly born infants, crave pure spiritual milk, so that you may be enabled by it to grow till you attain Salvation--

General references

Mark 10:15
I tell you, unless a man receives the Kingdom of God like a child, he will not enter it at all."
Luke 9:46
A discussion arose among the disciples as to which of them was the greatest;
Luke 22:26
But with you it must not be so. No, let the greatest among you become like the youngest, and him who leads like him who serves.
Acts 8:19
"Give me also this power of yours, so that, if I place my hands upon any one, he may receive the Holy Spirit."