When Was Moshe Rabbeinu’s Bris Before or After Megillah

להיות עשים את יום ארבעה עשר לחדש אדר ... בכל שנה ושנה

“To observe annually the fourteenth day of Adar.” (Esther 9:21)

Moshe Rabbeinu was born on the seventh of Adar, thus his bris took place on the 14th day of Adar, which is Purim. Was the bris performed before the reading of the Megillah or after?

Moshe was a great tzaddik and he died on the same day he was born. Since Moshe passed away on Shabbos, he was also born on Shabbos. Thus, his bris took place eight days later on Shabbos — 14 days into the month of Adar. Since it was Shabbos, the reading of the Megillah took place on Thursday the 12th of Adar.