Some scholars say an oath is not a yamin unless 'by Allah' is said

Ibrahim says that when a person says, "I make you swear," then there is nothing upon him, and when he says, "You are made to swear by the name of Allah," then this is an expiation for an oath.

Hazrat Ibn Jurayj says that I heard from Hazrat Ata, he says that an oath is not considered an oath until one says: I swear by the name of Allah.

Hasan says that when a person says, "I swear" or "I bear witness," and does not mention the name of Allah, then there is nothing upon him.

Hazrat Zuhri says that when a person says, "I swear," or "I testify," or "I take an oath," then until it is with the name of Allah, it is not considered an oath.

Hazrat Ibn al-Hanafiyyah says that when a person says, "I swear an oath," then until it is with the name of Allah, it is not an oath.

12728 - From (1) a man from Ibn (al-Hanafiyyah) (2) (they both said) (3): If a man says: "I swear," it is not an oath until he says: "By Allah."