What does 1 Chronicles 23:31 mean?

and to offer all burnt-offerings unto Jehovah, on the sabbaths, on the new moons, and on the set feasts, in number according to the ordinance concerning them, continually before Jehovah;

And to offer all burnt sacrifices unto the Lord in the sabbaths, in the new moons, and on the set feasts, by number, according to the order commanded unto them, continually before the Lord:

and to offer all burnt-offerings unto Jehovah, on the sabbaths, on the new moons, and on the set feasts, in number according to the ordinance concerning them, continually before Jehovah;

At every offering of burned offerings to the Lord, on Sabbaths, and at the new moons, and on the regular feasts, in the number ordered by the law, at all times before the Lord;

and for all the burnt-offerings--burnt-offerings to Jehovah for sabbaths, for new moons, and for appointed seasons, by number, according to the ordinance upon them continually, before Jehovah.

As well in the oblation of the holocausts of the Lord, as in the sabbaths and in the new moons, and the rest of the solemnities, according to the number and ceremonies prescribed for every thing, continually before the Lord.

and for all burnt-offerings offered up to Jehovah on the sabbaths, on the new moons, and on the set feasts, by number, according to the ordinance concerning them, continually, before Jehovah;