Matthew 7:14

Because narrow is the gate and constricted is the way which leads to life, and there are few who find it.

Acts 14:22

confirming the souls of the disciples, calling on them to continue in the faith and that through much tribulation we must enter into the kingdom of God.

Proverbs 4:26-27

Ponder the path of your feet, and all your ways will be established.

Proverbs 8:20

I lead in the way of righteousness, in the midst of the paths of judgment;

Isaiah 30:21

And your ears shall hear a word behind you, saying, This is the way, walk in it, when you turn to the right hand and when you turn to the left.

Isaiah 35:8

And a highway shall be there, and a way, and it shall be called, The Way of Holiness. The unclean shall not pass over it. But He shall be with them; the wayfaring men, though fools, shall not err in it.

Isaiah 57:14

And He shall say, Raise up! Raise up! Clear the way! Make the stumbling-block rise out of the way of My people.

Jeremiah 6:16

So says Jehovah, Stand in the ways and see, and ask for the old paths where the good way is, and walk in it, and you shall find rest for your souls. But they said, We will not walk in it.

Matthew 16:24-25

Then Jesus said to His disciples, If anyone desires to come after Me, let him deny himself and take up his cross and follow Me.

Matthew 20:16

So the last shall be first, and the first last, for many are called, but few are chosen.

Matthew 22:14

For many are called, but few chosen.

Matthew 25:1-12

Then shall the kingdom of Heaven be likened to ten virgins, who took their lamps and went out to meet the bridegroom.

Mark 8:34

And calling near the crowd with His disciples, He said to them, Whoever will come after Me, let him deny himself and take up his cross and follow Me.

Luke 12:32

Do not fear, little flock, for it is your Father's good pleasure to give you the kingdom.

Luke 13:23-30

And one said to Him, Lord, are the ones being saved few? And He said to them,

John 15:18-20

If the world hates you, you know that it hated Me before it hated you.

John 16:2

They shall put you out of the synagogue. But an hour is coming that everyone who kills you will think that he bears God service.

John 16:33

I have spoken these things to you so that you might have peace in Me. In the world you shall have tribulation, but be of good cheer. I have overcome the world.

Romans 9:27-29

Isaiah also cries concerning Israel, "Though the number of the sons of Israel is as the sands of the sea, a remnant shall be saved.

Romans 9:32

Why? Because it was not of faith, but as it were by the works of the Law. For they stumbled at that Stumbling-stone;

Romans 11:5-6

Even so then, also in this present time a remnant according to the election of grace has come into being.

Romans 12:2

And do not be conformed to this world, but be transformed by the renewing of your mind, in order to prove by you what is that good and pleasing and perfect will of God.

Ephesians 2:2-3

in which you once walked according to the course of this world, according to the prince of the power of the air, the spirit that now works in the children of disobedience;

1 Thessalonians 3:2-5

And we sent Timothy, our brother and minister of God, and our fellow laborer in the gospel of Christ, to establish you and to comfort you concerning your faith,

1 Peter 3:20-21

to disobeying ones, when once the long-suffering of God waited in the days of Noah, while the ark was being prepared (in which a few, that is, eight souls were saved through water);

Treasury of Scripture Knowledge

Summary

Because strait is the gate, and narrow is the way, which leadeth unto life, and few there be that find it.

Bible References

Because

Matthew 16:24
Then Jesus said to His disciples, If anyone desires to come after Me, let him deny himself and take up his cross and follow Me.
Proverbs 4:26
Ponder the path of your feet, and all your ways will be established.
Proverbs 8:20
I lead in the way of righteousness, in the midst of the paths of judgment;
Isaiah 30:21
And your ears shall hear a word behind you, saying, This is the way, walk in it, when you turn to the right hand and when you turn to the left.
Isaiah 35:8
And a highway shall be there, and a way, and it shall be called, The Way of Holiness. The unclean shall not pass over it. But He shall be with them; the wayfaring men, though fools, shall not err in it.
Isaiah 57:14
And He shall say, Raise up! Raise up! Clear the way! Make the stumbling-block rise out of the way of My people.
Jeremiah 6:16
So says Jehovah, Stand in the ways and see, and ask for the old paths where the good way is, and walk in it, and you shall find rest for your souls. But they said, We will not walk in it.
Mark 8:34
And calling near the crowd with His disciples, He said to them, Whoever will come after Me, let him deny himself and take up his cross and follow Me.
John 15:18
If the world hates you, you know that it hated Me before it hated you.
John 16:2
They shall put you out of the synagogue. But an hour is coming that everyone who kills you will think that he bears God service.
Acts 14:22
confirming the souls of the disciples, calling on them to continue in the faith and that through much tribulation we must enter into the kingdom of God.
1 Thessalonians 3:2
And we sent Timothy, our brother and minister of God, and our fellow laborer in the gospel of Christ, to establish you and to comfort you concerning your faith,

General references

Numbers 4:48
even those numbered of them were eight thousand, five hundred and eighty.
Proverbs 2:9
Then you shall understand righteousness and judgment and honesty, every good path.
Proverbs 14:12
There is a way which seems right to a man, but the end of it is the ways of death.
Matthew 22:14
For many are called, but few chosen.
Romans 3:17
and the way of peace they did not know."