Galatians 1:9

As I said before, so say I now again, if any man preach any other thing unto you, than that ye have received, hold him accursed.

Deuteronomy 4:2

Ye shall put nothing unto the word which I command you, neither do ought therefrom, that ye may keep the commandments of the LORD your God which I command you.

Deuteronomy 12:32-11

But whatsoever I command you, that take heed ye do: and put nought thereto, nor take ought therefrom.

Proverbs 30:6

Put thou nothing therefore unto his words, lest he reprove thee, and thou be found as a liar.

Romans 16:17

I beseech you, brethren: mark them which cause division, and give occasions of evil contrary to the doctrine which ye have learned; and avoid them.

2 Corinthians 1:17

When I thus wise was minded: Did I use lightness? Or think I carnally those things which I think, that with me should be "yea, yea," and "nay, nay?"

2 Corinthians 13:1-2

Now come I the third time unto you: "In the mouth of two or three witnesses shall everything stand."

Philippians 3:1

Moreover, my brethren, rejoice in the Lord. It grieveth me not to write one thing often to you. For to you it is a sure thing.

Philippians 4:4

Rejoice in the Lord always, and again I say rejoice.

Revelation 22:18-19

I testify unto every man that heareth the words of prophecy of this book: if any man shall add unto these things, God shall add unto him the plagues that are written in this book.

Treasury of Scripture Knowledge

Summary

As we said before, so say I now again, If any man preach any other gospel unto you than that ye have received, let him be accursed.

General references

Bible References

So

2 Corinthians 1:17
When I thus wise was minded: Did I use lightness? Or think I carnally those things which I think, that with me should be "yea, yea," and "nay, nay?"
2 Corinthians 13:1
Now come I the third time unto you: "In the mouth of two or three witnesses shall everything stand."
Philippians 3:1
Moreover, my brethren, rejoice in the Lord. It grieveth me not to write one thing often to you. For to you it is a sure thing.
Philippians 4:4
Rejoice in the Lord always, and again I say rejoice.

Than

Deuteronomy 4:2
Ye shall put nothing unto the word which I command you, neither do ought therefrom, that ye may keep the commandments of the LORD your God which I command you.
Deuteronomy 12:32
But whatsoever I command you, that take heed ye do: and put nought thereto, nor take ought therefrom.
Deuteronomy 13:1
If there arise among you a prophet or a dreamer of dreams, and give thee a sign or a wonder -
Proverbs 30:6
Put thou nothing therefore unto his words, lest he reprove thee, and thou be found as a liar.
Revelation 22:18
I testify unto every man that heareth the words of prophecy of this book: if any man shall add unto these things, God shall add unto him the plagues that are written in this book.

General references

Leviticus 15:8
If any such spit upon him that is clean, he must wash his clothes and bathe himself in water and be unclean until even.
1 Corinthians 3:11
For other foundation can no man lay, than that which is laid, which is Jesus Christ.