Deuteronomy 12:32

The whole thing which I am commanding you -- it ye observe to do; thou dost not add unto it, nor diminish from it.

Deuteronomy 4:2

Ye do not add to the word which I am commanding you, nor diminish from it, to keep the commands of Jehovah your God which I am commanding you.

Joshua 1:7

Only, be strong and very courageous, to observe to do according to all the law which Moses My servant commanded thee; thou dost not turn aside from it right or left, so that thou dost act wisely in every place whither thou goest;

Proverbs 30:6

Add not to His words, lest He reason with thee, And thou hast been found false.

Revelation 22:18-19

'For I testify to every one hearing the words of the prophecy of this scroll, if any one may add unto these, God shall add to him the plagues that have been written in this scroll,

Deuteronomy 13:18

when thou dost hearken to the voice of Jehovah thy God, to keep all his commands which I am commanding thee to-day, to do that which is right in the eyes of Jehovah thy God.

Matthew 28:20

teaching them to observe all, whatever I did command you,) and lo, I am with you all the days -- till the full end of the age.'

Treasury of Scripture Knowledge

Summary

What thing soever I command you, observe to do it: thou shalt not add thereto, nor diminish from it.

Bible References

Thou shalt not

Deuteronomy 4:2
Ye do not add to the word which I am commanding you, nor diminish from it, to keep the commands of Jehovah your God which I am commanding you.
Deuteronomy 13:18
when thou dost hearken to the voice of Jehovah thy God, to keep all his commands which I am commanding thee to-day, to do that which is right in the eyes of Jehovah thy God.
Joshua 1:7
Only, be strong and very courageous, to observe to do according to all the law which Moses My servant commanded thee; thou dost not turn aside from it right or left, so that thou dost act wisely in every place whither thou goest;
Proverbs 30:6
Add not to His words, lest He reason with thee, And thou hast been found false.
Matthew 28:20
teaching them to observe all, whatever I did command you,) and lo, I am with you all the days -- till the full end of the age.'
Revelation 22:18
'For I testify to every one hearing the words of the prophecy of this scroll, if any one may add unto these, God shall add to him the plagues that have been written in this scroll,

General references

Genesis 6:22
And Noah doth according to all that God hath commanded him; so hath he done.
Genesis 21:4
and Abraham circumciseth Isaac his son, being a son of eight days, as God hath commanded him.
Leviticus 8:4
And Moses doth as Jehovah hath commanded him, and the company is assembled unto the opening of the tent of meeting,
Numbers 1:54
And the sons of Israel do according to all that Jehovah hath commanded Moses; so they have done.
Deuteronomy 1:18
and I command you, at that time, all the things which ye do.
Deuteronomy 4:2
Ye do not add to the word which I am commanding you, nor diminish from it, to keep the commands of Jehovah your God which I am commanding you.
Deuteronomy 11:32
and observed to do all the statutes and the judgments which I am setting before you to day.
Psalm 119:4
Thou hast commanded us Thy precepts to keep diligently,