It's one of the unwritten rules in the Bible, along with:
-Close eyes when praying
-Speaking in a dead form of English
-holding hands together while praying
------specific to the culture of where I go to church-----
-Saying "Lord God" or "Father God" after like literally every other word almost during a prayer.
-Coffee blacker than the center of a black hole.
-Beards
-Always have a knife on you.
-Hipster dresscode
What? No "Lord Jesus" or "Christ Jesus" or the like? What are they, Unitarians? Probably not, tho. Most Unitarians would throw in a "Mother Goddess" or two as well.
Far from Unitarian, and last I checked it was aMEN, not aWOMAN.