In the beginnings of your months. The new-moon offering also is here enjoined for the first time, the festival itself having only been incidentally mentioned in Numbers 10:10. There can be no doubt that this (unlike the sabbath) was a nature-festival, observed more or less by all nations.
As such it did not require to be instituted, but only to be regulated and sanctified in order that it might not lend itself to idolatry, as it did among the heathen (cf. Deuteronomy 4:19; Job 31:26, Job 31:27; Jeremiah 7:18; Jeremiah 8:2).
The new-moon feast, depending upon no calendar but that of the sky, and more clearly marked in that than any other recurring period, was certain to fix itself deeply in the social and religious habits of a simple pastoral or agricultural people.
Accordingly we find it incidentally mentioned as a day of social gathering (1 Samuel 20:5), and as a day for religious instruction (2 Kings 4:23). From the latter passage, and from such passages as Isaiah 66:23; Ezekiel 46:1; Amos 8:5, it is evident that the feast of the new moon became to the month exactly what the sabbath was to the week—a day of rest and of worship (see also Judith 8:6).