Bible Verses About Months: Commenced with first appearance of new moon

Also in the day of your gladness, and in your solemn days, and in the beginnings of your months, ye shall blow with the trumpets over your burnt offerings, and over the sacrifices of your peace offerings; that they may be to you for a memorial before your God: I am the LORD your God.

Blow up the trumpet in the new moon, in the time appointed, on our solemn feast day.