As for those who strive in Us,
We surely guide them to Our paths (Quran)
"...it is recorded a woman said to A'isha: "O mother." She said: "I'm not your mother but I'm the mother of your men." And that is the right opinion....
Source: Tafsir ibn Arabi. Vol. 3, Pg. # 542.
Available From: "Revisiting The Salaf" Blog, with some editions.
The following narration shows that what is meant by referring to the prophet's wives as the mother of the believers, is that men are not allowed to marry them after the death of the prophet SAAW: