Numbers 8:18

16 For the Levites have been wholly given to Me from among the sons of Israel. I have taken them for Myself in place of all who come first from the womb, the firstborn of all the sons of Israel.

17 For every firstborn male in Israel is Mine, both man and beast. I set them apart for Myself on the day I struck down all the firstborn in the land of Egypt.

But I have taken the Levites in place of all the firstborn among the sons of Israel.

19 And I have given the Levites as a gift to Aaron and his sons from among the Israelites, to perform the service for the Israelites at the Tent of Meeting and to make atonement on their behalf, so that no plague will come against the Israelites when they approach the sanctuary.”

20 So Moses, Aaron, and the whole congregation of Israel did with the Levites everything that the LORD had commanded Moses they should do.

This was said to Israel at a particular time, so it is wise to read it together with the surrounding text. Do read the surrounding verses too, because the context often says more than a single verse.

Compare

BSB
But I have taken the Levites in place of all the firstborn among the sons of Israel.
KJV
And I have taken the Levites for all the firstborn of the children of Israel.
WEB
I have taken the Levites instead of all the firstborn among the children of Israel.
ASV
And I have taken the Levites instead of all the first-born among the children of Israel.
DARBY
And I have taken the Levites instead of all the firstborn among the children of Israel.
BLB
And I have taken the Levites instead of all the firstborn of the sons of Israel.
ÅB
Men nå har jeg tatt levittene i stedet for alle førstefødte blant Israels barn.
OTB
Jeg har tatt levittene i stedet for hver førstefødt blant israelittene.
B1930
Men nu har jeg tatt levittene i stedet for alle førstefødte blandt Israels barn.

Study notes (Tyndale)

Original text and word study