Numbers 18:26

Say to the Levites, When you take from the children of Israel the tenth which I have given to you from them as your heritage, a tenth part of that tenth is to be offered as an offering lifted up before the Lord.

Nehemiah 10:38

And the priest, the son of Aaron, is to be with the Levites, when the Levites take the tenths: and the Levites are to take a tenth of the tenths into the house of our God, to the rooms, into the store-house;

Numbers 18:21

And to the children of Levi I have given as their heritage all the tenths offered in Israel, as payment for the work they do, the work of the Tent of meeting.

Treasury of Scripture Knowledge

Summary

Thus speak unto the Levites, and say unto them, When ye take of the children of Israel the tithes which I have given you from them for your inheritance, then ye shall offer up an heave offering of it for the LORD, even a tenth part of the tithe.

Then ye shall

A tenth part

General references

Bible References

Then ye shall

Numbers 18:19
All the lifted offerings of the holy things which the children of Israel give to the Lord, I have given to you and to your sons and to your daughters as a right for ever. This is an agreement made with salt before the Lord, to you and to your seed for ever.

A tenth part

Nehemiah 10:38
And the priest, the son of Aaron, is to be with the Levites, when the Levites take the tenths: and the Levites are to take a tenth of the tenths into the house of our God, to the rooms, into the store-house;

General references

Numbers 15:21
From generation to generation you are to give to the Lord a lifted offering from the first of your rough meal.

Basic English, produced by Mr C. K. Ogden of the Orthological Institute - public domain