1 John 2:19

They went out from among us, but they were not of us; for if they had been of us, they would have surely remained with us, but that they might be made manifest that none are of us.

Acts 20:30

and from among your own selves shall rise up men speaking perverted things to draw away the disciples after them.

1 Corinthians 11:19

For there must also be sects among you, that the approved may become manifest among you.

Deuteronomy 13:13

There are men, children of Belial, gone out from among you, and they have drawn away the inhabitants of their city, saying, Let us go and serve other gods, whom ye have not known;

Job 17:9

But the righteous shall hold on his way, and he that hath clean hands shall increase in strength.

Psalm 37:28

for Jehovah loveth judgment, and will not forsake his saints: They are preserved for ever; but the seed of the wicked shall be cut off.

Psalm 41:9

Yea, mine own familiar friend, in whom I confided, who did eat of my bread, hath lifted up his heel against me.

Psalm 125:1-2

{A Song of degrees.} They that confide in Jehovah are as mount Zion, which cannot be moved; it abideth for ever.

Jeremiah 32:38-40

And they shall be my people, and I will be their God.

Matthew 13:20-21

But he that is sown on the rocky places this is he who hears the word and immediately receives it with joy,

Matthew 24:24

For there shall arise false Christs, and false prophets, and shall give great signs and wonders, so as to mislead, if possible, even the elect.

Mark 4:5-6

And another fell on the rocky ground, where it had not much earth, and immediately it sprung up out of the ground because it had no depth of earth;

Mark 4:16-17

And these are they in like manner who are sown upon the rocky places, who when they hear the word, immediately receive it with joy,

Mark 13:22

For false Christs and false prophets will arise, and give signs and wonders to deceive, if possible, even the elect.

Luke 8:13

But those upon the rock, those who when they hear receive the word with joy; and these have no root, who believe for a time, and in time of trial fall away.

John 4:14

but whosoever drinks of the water which I shall give him shall never thirst for ever, but the water which I shall give him shall become in him a fountain of water, springing up into eternal life.

John 6:37-39

All that the Father gives me shall come to me, and him that comes to me I will not at all cast out.

John 10:28-30

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

John 15:2

As to every branch in me not bearing fruit, he takes it away; and as to every one bearing fruit, he purges it that it may bring forth more fruit.

Acts 15:24

Inasmuch as we have heard that some who went out from amongst us have troubled you by words, upsetting your souls, saying that ye must be circumcised and keep the law; to whom we gave no commandment;

Romans 9:6

Not however as though the word of God had failed; for not all are Israel which are of Israel;

Romans 11:5-6

Thus, then, in the present time also there has been a remnant according to election of grace.

2 Timothy 2:10

For this cause I endure all things for the sake of the elect, that they also may obtain the salvation which is in Christ Jesus with eternal glory.

2 Timothy 2:19

Yet the firm foundation of God stands, having this seal, The Lord knows those that are his; and, Let every one who names the name of the Lord withdraw from iniquity.

2 Timothy 3:9

But they shall not advance farther; for their folly shall be completely manifest to all, as that of those also became.

Hebrews 10:39

But we are not drawers back to perdition, but of faith to saving the soul.

1 Peter 1:2-5

elect according to the foreknowledge of God the Father, by sanctification of the Spirit, unto the obedience and sprinkling of the blood of Jesus Christ: Grace to you and peace be multiplied.

2 Peter 2:20-21

For if after having escaped the pollutions of the world through the knowledge of the Lord and Saviour Jesus Christ, again entangled, they are subdued by these, their last state is worse than the first.

Jude 1:1

Jude, bondman of Jesus Christ, and brother of James, to the called ones beloved in God the Father and preserved in Jesus Christ:

Jude 1:19

These are they who set themselves apart, natural men, not having 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

Deuteronomy 13:13
There are men, children of Belial, gone out from among you, and they have drawn away the inhabitants of their city, saying, Let us go and serve other gods, whom ye have not known;
Psalm 41:9
Yea, mine own familiar friend, in whom I confided, who did eat of my bread, hath lifted up his heel against me.
Matthew 13:20
But he that is sown on the rocky places this is he who hears the word and immediately receives it with joy,
Mark 4:5
And another fell on the rocky ground, where it had not much earth, and immediately it sprung up out of the ground because it had no depth of earth;
Luke 8:13
But those upon the rock, those who when they hear receive the word with joy; and these have no root, who believe for a time, and in time of trial fall away.
John 15:2
As to every branch in me not bearing fruit, he takes it away; and as to every one bearing fruit, he purges it that it may bring forth more fruit.
Acts 15:24
Inasmuch as we have heard that some who went out from amongst us have troubled you by words, upsetting your souls, saying that ye must be circumcised and keep the law; to whom we gave no commandment;
Acts 20:30
and from among your own selves shall rise up men speaking perverted things to draw away the disciples after them.
2 Peter 2:20
For if after having escaped the pollutions of the world through the knowledge of the Lord and Saviour Jesus Christ, again entangled, they are subdued by these, their last state is worse than the first.
Jude 1:19
These are they who set themselves apart, natural men, not having the Spirit.

They might

Romans 9:6
Not however as though the word of God had failed; for not all are Israel which are of Israel;
Romans 11:5
Thus, then, in the present time also there has been a remnant according to election of grace.
1 Corinthians 11:19
For there must also be sects among you, that the approved may become manifest among you.
2 Timothy 3:9
But they shall not advance farther; for their folly shall be completely manifest to all, as that of those also became.
Hebrews 10:39
But we are not drawers back to perdition, but of faith to saving the soul.

General references

Matthew 25:2
And five of them were prudent and five foolish.
John 10:5
But they will not follow a stranger, but will flee from him, because they know not the voice of strangers.
1 Timothy 5:15
For already some have turned aside after Satan.