In Exodus they don't have to say that the month begins with the new moon because everyone knew it--most ancient societies had lunar calendars (inserting an extra month every second or third year to keep the year in line with the solar year so that seasonal feasts would fall at the right time of year). The Muslims still have a lunar calendar, but Muhammed forbade inserting the extra months, so their months come about 11 days earlier every year compared to ours.
See Isaiah 1.14--"Your new moons and your appointed feasts my soul hateth..."--the lunar calendar was taken for granted.
In Exodus they don't have to say that the month begins with the new moon because everyone knew it--most ancient societies had lunar calendars (inserting an extra month every second or third year to keep the year in line with the solar year so that seasonal feasts would fall at the right time of year). The Muslims still have a lunar calendar, but Muhammed forbade inserting the extra months, so their months come about 11 days earlier every year compared to ours. See Isaiah 1.14--"Your new moons and your appointed feasts my soul hateth..."--the lunar calendar was taken for granted. God says *YOUR* new moons and *YOUR* appointed feasts *MY soul hateth: they are a *TROUBLE* unto ME: I am weary to bear them.
Now I ask you what part of this Scripture gives credence or credibility that the moon or anything lunar is part of a Heavenly Godly calendar. We have God saying His very inner Being HATES.
Now was not the moon described in Genesis as the lessor light and the moon gives no light of it own it 'steals' light from the *SUN* else we would never know it was there. SUN --- SON, so the solar calendar is the reliable calendar, and the moon is never known to be a reliable source of charting time.
When does spring begin... counting from there is Passover, no matter what the moon is doing.