All praise is due to Allah, and may Allah’s peace and blessings be upon the Messenger of Allah. To proceed:
The ruling on the phrase “O blessing of Allah’s Name” varies according to the speaker’s intention. If the person intends to express amazement at the blessing of mentioning Allah’s Name, or intends to ask Allah Almighty for blessing, then there is no harm in it. However, if the person intends to call upon “the blessing” itself and asks it to bring benefit or repel harm, then this is supplication directed to an attribute, which is prohibited and may reach the level of shirk.
Saying Bismillah is among the great forms of remembrance that a Muslim is encouraged to say when beginning important matters.
The Prophet ﷺ said:
“When night falls—or when the evening begins—keep your children close, for the devils spread out at that time. When an hour of the night has passed, let them go. Close your door and mention the Name of Allah, extinguish your lamp and mention the Name of Allah, tie your waterskin and mention the Name of Allah, and cover your vessel and mention the Name of Allah...”
Narrated by al-Bukhari.
The Prophet ﷺ also said:
“Whoever says: ‘In the Name of Allah, with whose Name nothing on earth or in heaven can cause harm, and He is the All-Hearing, the All-Knowing,’ nothing will harm him.”
Narrated by Ahmad and Abu Dawud.
Thus, mentioning the Name of Allah Almighty is a great cause of goodness, blessing, and protection, by Allah’s permission.
If a person says:
“O blessing of Allah’s Name”
while intending to express amazement at the great blessing that Allah has placed in mentioning His Name—for example, when seeing something remarkable or beneficial—then there is no harm in that.
The intention here is not to supplicate to the blessing itself, but rather to express amazement at the effect and blessing of mentioning Allah’s Name.
A person may also intend by saying:
“O blessing of Allah’s Name”
to ask that blessing be granted, meaning: “O Lord, grant me a share of the blessing of Your Name and Your remembrance.”
If the true intention is to supplicate to Allah Almighty and ask Him for blessing, rather than to supplicate to the blessing itself, then there is no harm in that.
Shaykh Ibn ‘Uthaymin, may Allah have mercy on him, was asked about a person saying: “O mercy of Allah.” He explained that the ruling depends on the speaker’s intention. If the person means to seek relief through Allah’s mercy—that is, he wants Allah Almighty to encompass him with His mercy—then this is permissible. But if he is calling upon the mercy itself and asking it to act independently, then that is different.
If, however, by saying “O blessing of Allah’s Name,” the speaker intends that he is calling upon the blessing itself, asking it to bring him good or repel harm from him, then this is not permissible.
The attributes of Allah Almighty are not supplicated to independently. Rather, Allah Himself is supplicated to by means of His attributes. For example, one may say:
“O Allah, by Your mercy, have mercy on me.”
But one should not say: “O mercy of Allah, have mercy on me,” intending to call upon the mercy itself.
Shaykh al-Islam Ibn Taymiyyah, may Allah have mercy on him, stated that asking Allah by His Names, Attributes, and Words is legislated, whereas calling upon His Attributes and Words themselves is not legislated, because an attribute does not act independently, nor does it independently bring benefit or repel harm.
Shaykh Ibn ‘Uthaymin, may Allah have mercy on him, also explained that supplicating to an attribute involves treating it as though it were independently capable of acting, bringing good, and repelling evil. This is the reason for the prohibition, and depending on the belief of the person making the supplication, it may reach the level of shirk.
The ruling on saying “O blessing of Allah’s Name” depends on what is intended:
It is preferable to use clear expressions, such as:
“O Allah, bless me”
or:
“O Allah, grant me from Your blessing,”
so that the intended meaning remains clear and free from ambiguity.
And Allah knows best.