Numbers 3:12

“Behold, I have taken the Levites from among the children of Israel in place of every firstborn Israelite from the womb. The Levites belong to Me,
BSB · Berean Standard Bible
And I, behold, I have taken the Levites from among the children of Israel instead of all the firstborn that openeth the matrix among the children of Israel: therefore the Levites shall be mine;
KJV · King James Version
“Behold, I have taken the Levites from among the children of Israel instead of all the firstborn who open the womb among the children of Israel; and the Levites shall be mine,

Note “Behold”, from “הִנֵּה”, means look at, take notice, observe, see, or gaze at. It is often used as an interjection.

WEB · World English Bible
And I, behold, I have taken the Levites from among the children of Israel instead of all the first-born that openeth the womb among the children of Israel; and the Levites shall be mine:
ASV · American Standard Version

Related passages

From the Treasury of Scripture Knowledge, grouped by the word they explain.

Numbers 3:12
When God miraculously destroyed all the first-born of the Egyptians, (Ex 12:29,) he spared those of the Israelites; and, in commemoration of that event, he was pleased to appoint that all the first-born males "should be set apart unto himself." (Ex 13:12-16.) God is here pleased to relinquish this claim, and to appoint the whole tribe of Levi to attend his immediate service in their stead.
Numbers 3:41, 45; Numbers 8:16, 18; Numbers 18:6