Charles Ellicott Commentary Numbers 1:18

"And they assembled all the congregation together on the first day of the second month; and they declared their pedigrees after their families, by their fathers` houses, according to the number of the names, from twenty years old and upward, by their polls." — Numbers 1:18 (ASV)

Declared their pedigrees.—More literally, announced themselves as having been born—that is, they caused themselves to be enrolled.

The people appear to have been enrolled by their polls, i.e., individually, under three headings:

1. according to the tribe to which they belonged;
2. according to the mishpahah, or family, which, as it appears from Numbers 3:22, included in some cases two or three thousand persons; and
3. according to their father’s house.

The importance of this enrolment, as providing the means of tracing the genealogy of Christ, must not be overlooked.

According to the number of the names.—The words are the same as in Numbers 1:2, and should be rendered in the same way.