The Moon: First Appearance of, a Time of Festivity
Source: TTT
1 Samuel 20:5, 6
So David told him, “Look, tomorrow is the New Moon, and I am supposed to dine with the king. Instead, let me go and hide in the field until the third evening from now. / If your father misses me at all, tell him, ‘David urgently requested my permission to hurry to Bethlehem, his hometown, because there is an annual sacrifice for his whole clan.’
Psalm 81:3
Sound the ram’s horn at the New Moon, and at the full moon on the day of our Feast.