Numbers 8:17
“For all the firstborn of the children of Israel are mine, both man and beast: on the day that I smote every firstborn in the land of Egypt I sanctified them for myself.”
And after that shall the Levites go in to do the service of the tabernacle of the congregation: and thou shalt cleanse them, and offer them for an offering.
For they are wholly given unto me from among the children of Israel; instead of such as open every womb, even instead of the firstborn of all the children of Israel, have I taken them unto me.
For all the firstborn of the children of Israel are mine, both man and beast: on the day that I smote every firstborn in the land of Egypt I sanctified them for myself.
And I have taken the Levites for all the firstborn of the children of Israel.
And I have given the Levites as a gift to Aaron and to his sons from among the children of Israel, to do the service of the children of Israel in the tabernacle of the congregation, and to make an atonement for the children of Israel: that there be no plague among the children of Israel, when the children of Israel come nigh unto the sanctuary.
Why This Verse Was Tagged
This verse contains specific terms directly associated with this theme.
Counter-Arguments
The strongest case that this verse does not belong in this theme.

Cross-References
“And it came to pass, that at midnight the Lord smote all the firstborn in the land of Egypt, from the firstborn of Pharaoh that sat on his throne unto the firstborn of the captive that was in the dungeon; and all the firstborn of cattle.”
“That thou shalt set apart unto the Lord all that openeth the matrix, and every firstling that cometh of a beast which thou hast; the males shall be the Lord’s.”
“Thus shalt thou separate the Levites from among the children of Israel: and the Levites shall be mine.”
“And for their sakes I sanctify myself, that they also might be sanctified through the truth.”
“Of his own will begat he us with the word of truth, that we should be a kind of firstfruits of his creatures.”