1 John 2:19

They went out from us, but they were not of us; for if they had been of us, they would have continued with us; but they went out that it might be plain that none of them were of us.

Acts 20:30

and from among your own selves will arise men speaking perverse things, to draw away the disciples after them.

1 Corinthians 11:19

For there must be factions among you in order that those who are genuine among you may be recognized.

Matthew 13:20-21

But he who received the seed on rocky places, this is he who hears the word and immediately receives it with joy;

Matthew 24:24

For false christs and false prophets will arise and show great signs and wonders to deceive, if possible, even the elect.

Mark 4:5-6

Some fell on rocky ground, where it did not have much soil, and immediately it sprang up, because it had no depth of soil.

Mark 4:16-17

And these likewise are the ones sown on rocky ground who, when they hear the word, immediately receive it with joy;

Mark 13:22

For false christs and false prophets will rise and show signs and wonders to deceive, if possible, even the elect.

Luke 8:13

And the ones on the rock are those who, when they hear the word, receive it with joy; but these have no root, they believe for a while and in time of temptation fall away.

John 4:14

but whoever drinks of the water that I shall give him will never thirst. The water that I shall give him will become in him a spring of water welling up to eternal life."

John 6:37-39

All that the Father gives me will come to me, and the one who comes to me I will by no means cast out.

John 10:28-30

I give them eternal life, and they shall never perish; no one shall snatch them out of my hand.

John 15:2

Every branch in me that bears no fruit he takes away; and every branch that does bear fruit he prunes, so that it may bear more fruit.

Acts 15:24

Since we have heard that some persons from us have disturbed you with words, unsettling your minds, although we gave them no instructions,

Romans 9:6

But it is not as though the word of God had failed. For not all who are descended from Israel are Israel,

Romans 11:5-6

So too at the present time there is a remnant, chosen by grace.

2 Timothy 2:10

Therefore I endure everything for the sake of the elect, that they too may obtain the salvation that is in Christ Jesus, with eternal glory.

2 Timothy 2:19

Nevertheless, God's firm foundation stands, having this seal: "The Lord knows those who are his," and, "Everyone who names the name of the Lord must turn away from wickedness."

2 Timothy 3:9

But they will not get very far, for their folly will be plain to all, as was that of those two men.

Hebrews 10:39

But we are not of those who shrink back and are destroyed, but of those who have faith and keep their souls.

1 Peter 1:2-5

who have been chosen according to the foreknowledge of God the Father, by the sanctifying work of the Spirit, for obedience to Jesus Christ and sprinkling with his blood: may grace and peace be yours in abundance.

2 Peter 2:20-21

For if, after they have escaped the defilements of the world by the knowledge of the Lord and Savior Jesus Christ, they are again entangled in them and are overcome, the last state has become worse for them than the first.

Jude 1:1

Jude, a servant of Jesus Christ and brother of James, to those who are called, beloved in God the Father and kept for Jesus Christ:

Jude 1:19

These are the ones who cause divisions, worldly-minded, devoid of the Spirit.

Treasury of Scripture Knowledge

Summary

They went out from us, but they were not of us; for if they had been of us, they would no doubt have continued with us: but they went out, that they might be made manifest that they were not all of us.

Bible References

Went out

Matthew 13:20
But he who received the seed on rocky places, this is he who hears the word and immediately receives it with joy;
Mark 4:5
Some fell on rocky ground, where it did not have much soil, and immediately it sprang up, because it had no depth of soil.
Luke 8:13
And the ones on the rock are those who, when they hear the word, receive it with joy; but these have no root, they believe for a while and in time of temptation fall away.
John 15:2
Every branch in me that bears no fruit he takes away; and every branch that does bear fruit he prunes, so that it may bear more fruit.
Acts 15:24
Since we have heard that some persons from us have disturbed you with words, unsettling your minds, although we gave them no instructions,
Acts 20:30
and from among your own selves will arise men speaking perverse things, to draw away the disciples after them.
2 Peter 2:20
For if, after they have escaped the defilements of the world by the knowledge of the Lord and Savior Jesus Christ, they are again entangled in them and are overcome, the last state has become worse for them than the first.
Jude 1:19
These are the ones who cause divisions, worldly-minded, devoid of the Spirit.

They might

Romans 9:6
But it is not as though the word of God had failed. For not all who are descended from Israel are Israel,
Romans 11:5
So too at the present time there is a remnant, chosen by grace.
1 Corinthians 11:19
For there must be factions among you in order that those who are genuine among you may be recognized.
2 Timothy 3:9
But they will not get very far, for their folly will be plain to all, as was that of those two men.
Hebrews 10:39
But we are not of those who shrink back and are destroyed, but of those who have faith and keep their souls.

General references

Matthew 25:2
Five of them were foolish, and five were wise.
John 10:5
A stranger they will not follow, but they will flee from him, for they do not know the voice of strangers."
1 Timothy 5:15
For some have already turned aside to follow Satan.