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 they might be made manifest, that they were not all of us.

Acts 20:30

Yea, from among yourselves men will arise, speaking perverse things, to draw away disciples after them.

1 Corinthians 11:19

For there must be heresies also among you, that the approved among you may be manifest).

Matthew 13:20-21

But he who received the seed in stony places, is he that heareth the word, and immediately receiveth it with joy.

Matthew 24:24

For false Christs and false prophets shall arise and shew great signs and wonders, so that they would deceive (if it were possible) even the elect.

Mark 4:5-6

And some fell on stony ground, where it had not much earth; and immediately it sprung up, because it had no depth of earth.

Mark 4:16-17

And these are they likewise who have received the seed on stony ground, who when they have heard the word, immediately receive it with joy: But have not root in themselves, and so indure but for a time:

Mark 13:22

For false Christs and false prophets shall rise, and shall shew signs and wonders, to seduce, if it were possible, even the elect.

Luke 8:13

Those on the rock are they, who, when they hear, receive the word with joy. But they have no root, who for a while believe; but in time of temptation fall away.

John 4:14

But whosoever drinketh of the water that I shall give him, will never thirst; but the water that I shall give him, will be in him a fountain of water, springing up into everlasting life.

John 6:37-39

All that the Father giveth me, will come to me, and him that cometh to me, I will in no wise cast out.

John 10:28-30

And I give them eternal life, and they shall never perish, neither shall any pluck them out of my hand.

John 15:2

and every one that beareth fruit, he purifieth it, that it may bear more fruit.

Acts 15:24

Forasmuch as we have heard, that some who came from us have troubled you with words, unsettling your minds, saying, Ye must be circumcised, and keep the law, whom we commanded not.

Romans 9:6

Not as if the word of God had fallen to the ground; for all are not Israel, who are of Israel.

Romans 11:5-6

And so likewise at the present time, there is a remnant, according to the election of grace.

2 Timothy 2:10

Therefore I suffer all things for the elect's sake, that they also may obtain the salvation which is through Christ Jesus, with eternal glory.

2 Timothy 2:19

But the foundation of God standeth fast, having this seal, The Lord knoweth those that are his: and, Let every one who nameth the name of the Lord depart from iniquity.

2 Timothy 3:9

But they shall proceed no farther; for their folly shall be manifest to all men, as theirs also was.

Hebrews 10:39

But we are not of them who draw back to perdition, but of them that believe to the saving of the soul.

1 Peter 1:2-5

Galatia, Cappadocia, Asia, and Bithynia, Elect (according to the fore-knowledge of God the Father) thro' sanctification of the Spirit unto obedience and sprinkling of the blood of Jesus Christ. Grace and peace be multiplied to you.

2 Peter 2:20-21

For if after they have escaped the pollutions of the world, thro the knowledge of the Lord and Saviour Jesus Christ, they are again intangled therein and overcome, their last state is worse then the first.

Jude 1:1

Jude, a servant of Jesus Christ, and brother of James, to them that are beloved of God the Father, and preserved through Jesus Christ,

Jude 1:19

These are they who separate themselves, sensual, 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

Matthew 13:20
But he who received the seed in stony places, is he that heareth the word, and immediately receiveth it with joy.
Mark 4:5
And some fell on stony ground, where it had not much earth; and immediately it sprung up, because it had no depth of earth.
Luke 8:13
Those on the rock are they, who, when they hear, receive the word with joy. But they have no root, who for a while believe; but in time of temptation fall away.
John 15:2
and every one that beareth fruit, he purifieth it, that it may bear more fruit.
Acts 15:24
Forasmuch as we have heard, that some who came from us have troubled you with words, unsettling your minds, saying, Ye must be circumcised, and keep the law, whom we commanded not.
Acts 20:30
Yea, from among yourselves men will arise, speaking perverse things, to draw away disciples after them.
2 Peter 2:20
For if after they have escaped the pollutions of the world, thro the knowledge of the Lord and Saviour Jesus Christ, they are again intangled therein and overcome, their last state is worse then the first.
Jude 1:19
These are they who separate themselves, sensual, not having the Spirit.

They might

Romans 9:6
Not as if the word of God had fallen to the ground; for all are not Israel, who are of Israel.
Romans 11:5
And so likewise at the present time, there is a remnant, according to the election of grace.
1 Corinthians 11:19
For there must be heresies also among you, that the approved among you may be manifest).
2 Timothy 3:9
But they shall proceed no farther; for their folly shall be manifest to all men, as theirs also was.
Hebrews 10:39
But we are not of them who draw back to perdition, but of them that believe to the saving of the soul.

General references

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