'New moon' in the Bible
And David said to Jonathan, Behold, to morrow is the new-moon, and I should not fail to sit with the king at meat: but let me go, that I may hide myself in the field to the third day at evening.
Then Jonathan said to David, To-morrow is the new-moon: and thou wilt be missed, because thy seat will be empty.
So David hid himself in the field: and when the new-moon had come, the king sat down to eat food.
{And then} on the next day, the second day of the new moon, that David's place was empty. So Saul asked Jonathan his son, "Why did the son of Jesse not come either yesterday or today to the feast?"
Jonathan got up from the table {enraged}, and did not eat on the second day of the new moon because he was upset about David, because his father had disgraced him.