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

"Also on your days of rejoicing, at your designated times and on Rosh-Hodesh, you are to sound the trumpets over your burnt offerings and over the sacrifices of your peace offerings; these will be your reminder before your God. I am ADONAI your God."

Sound the shofar at Rosh-Hodesh and at full moon for the pilgrim feast,