Since Rosh Hashanah and Yom Kippur are the most sacred days of the Jewish calendar, why would an atheist Jew like me note these high holidays? And I’m by no means unique. There are atheist Jews in Reform, Conservative, and even Orthodox congregations. And the openly nontheistic Society for Humanistic Judaism celebrates all the Jewish holidays.

Regardless of belief, there is a one-word reason why most Jews remember Jewish holidays—God. Without that concept, there would be no Jews. So I’m happy to credit God for the holidays, even if he/she/it doesn’t exist. I commemorate this time of year partly due to my Jewish tradition, but also because I want to help change that tradition into a more godless one.

There are two religious reasons for celebrating the Jewish New Year of Rosh Hashanah. One is bad, and the other is worse. Here’s the bad: Rosh Hashanah commemorates the scientifically indefensible anniversary of the creation of the world, 5,774 years ago. And here’s worse: It’s also the anniversary of Abraham agreeing to kill his son Isaac, as proof of his faith and obedience to God. This Torah portion in Genesis 22 is read every Rosh Hashanah.

That biblical passage also refers to Isaac as Abraham’s only son, which means his first-born son Ishmael doesn’t count. Why? Because Isaac’s mother, Sarah, was Jewish and Ishmael’s mother was merely Sarah’s gentile servent whom Sarah lent to Abraham when she thought she was barren. On the other hand, in Islamic tradition it is Ishmael and not Isaac who was to be sacrificed by Abraham. And Muhammad is believed to be a direct descendent of Ishmael.