About the fatwa
Ruling on saying “Ya Rahmat Allaah (O Mercy of Allaah)”
What is the ruling on what some people say, “Ya Rahmat Allaah (O Mercy of Allaah)”?
Answer
Praise be to Allaah.
This is not permitted, this is like calling upon one of the attributes of Allaah).
From Fataawa Samaahat al-Shakh Muhammad ibn Ibraaheem (may Allaah have mercy on him) 1/117