Charles Ellicott Commentary Nehemiah 10:36

"also the first-born of our sons, and of our cattle, as it is written in the law, and the firstlings of our herds and of our flocks, to bring to the house of our God, unto the priests that minister in the house of our God;" — Nehemiah 10:36 (ASV)

The firstborn of our sons, and of our cattle.—Similarly collocated in Numbers 16:15-16; but there the cattle are defined as “unclean beasts,” thus distinguished from “the firstlings of our herds and of our flocks.” The latter were to be brought to “the priests that minister” for sacrifice; the former were, with the sons, to be redeemed by money, according to the priests’ valuation.