John Gill Commentary 2 Chronicles 29:24

"and the priests killed them, and they made a sin-offering with their blood upon the altar, to make atonement for all Israel; for the king commanded [that] the burnt-offering and the sin-offering [should be made] for all Israel." — 2 Chronicles 29:24 (ASV)

And the priests killed them The seven he goats; for of the killing of the bullocks, rams, and lambs, mention is made before, (2 Chronicles 29:2) and they made reconciliation with their blood upon the altar, to make atonement for all Israel ; typical of the reconciliation and atonement made for the whole spiritual Israel of God by the sacrifice of Christ:

for the king commanded that the burnt offering, and the sin offering , should be made for all Israel ;

not only for the tribes of Judah and Benjamin, and for as many of the rest of the tribes as were come over to them, and dwelt among them; but even for the ten tribes also, sadly guilty of idolatry, and for whose reformation and good this pious prince was concerned, see (2 Chronicles 30:1) .