Psalm 104:19 says, "He made the moon for the seasons." How does the moon affect our seasons? — Robert of Palatine, IL

Dear Robert,

When we hear the word "seasons," we think of spring, summer, autumn and winter. We know that it is the tilt of the Earth's axis in relation to our orbit around the Sun that causes these four seasons, not the Moon. But the word "season" also means an appointed time. Ancient people knew that the Moon went through one of its cycles every 29½ days. They made each one of these cycles a month in their calendar. This was very important because they had to know when to plant their crops. In the Old Testament, God told His people to make the first day of each month a special day (Numbers 10:10). The person who wrote this psalm was thanking God for creating lightgivers like the Moon "for signs, and for seasons, for days, and years" (Genesis 1:14).