Take ye the sum of all the congregation of the children of Israel, after their families, by the house of their fathers, with the number of their names, every male by their polls;

Wesley's Notes

1:2 Take the sum - This is not the same muster with that Exo 38:26, as plainly appears, because that was before the building of the tabernacle, which was built and set up on the first day of the first month, Exo 40:2, but this was after it, on the first day of the second month. And they were for different ends; that was to tax them for the charges of the tabernacle; but this was for other ends, partly that the great number of the people might be known to the praise of God's faithfulness, in making good his promises of multiplying them, and to their own encouragement: partly for the better ordering their camp and march, for they were now beginning their journey; and partly that this account might he compared with the other in the close of the book, where we read that not one of all this vast number, except Caleb and Joshua were left alive; a fair warning to all future generations to take heed of rebelling against the Lord. It is true, the sums and numbers agree in this and that computation, which is not strange, because there was not much time between the two numberings, and no eminent sin among the people in that interval, whereby God was provoked to diminish their numbers. Some conceive that in that number, Exo 30:11 - 16 and 38:25,26, the Levites were included, which are here excepted, Num 1:47, and that in that interval of time, there were grown up as many more men of those years as there were Levites of the same age. Israel - So the strangers mixed with them, were not numbered. Their fathers - The people were divided into twelve tribes, the tribes into great families, Num 26:5, these great families into lesser families called the houses of their fathers, because they were distinguished one from another by their fathers.

Scofield Reference Notes

Margin second month

i.e. May; also Num 1:18.

Matthew Henry's Concise Commentary

1:1-43 The people were numbered to show God's faithfulness in thus increasing the seed of Jacob, that they might be the better trained for the wars and conquest of Canaan, and to ascertain their families in order to the division of the land. It is said of each tribe, that those were numbered who were able to go forth to war; they had wars before them, though now they met with no opposition. Let the believer be prepared to withstand the enemies of his soul, though all may appear to be peace.