The Prophet (ﷺ) said, "Whoever has to take an oath should swear by Allah or remain silent." (i.e. He should not swear by other than Allah.)
Hadith Text and Reference
The Prophet (ﷺ) said, "Whoever has to take an oath should swear by Allah or remain silent." (i.e. He should not swear by other than Allah.)
Reference: Sahih al-Bukhari 2679, Book: Witnesses
Commentary on the Prohibition
This hadith establishes the fundamental Islamic principle that oaths may only be sworn by Allah's name. Swearing by other than Allah - whether by prophets, Ka'bah, one's parents, or any created being - constitutes shirk (associating partners with Allah) in worship, as oath-taking is an act of devotion that must be directed solely to the Creator.
The command "or remain silent" indicates the gravity of this matter - it is better to refrain from swearing altogether than to commit shirk by swearing by other than Allah. This prohibition protects tawheed (monotheism) and prevents the sanctification of created beings.
Scholarly Elaboration
Imam Ibn Hajar al-Asqalani explains in Fath al-Bari that this hadith categorically forbids all forms of oath-taking except by Allah's attributes and names. The companions understood this prohibition strictly, with Ibn Umar reporting that even swearing by one's forefathers was forbidden during the Prophet's time.
Scholars differentiate between intentional swearing by other than Allah (major shirk) and habitual phrases used in common speech without oath intention. However, the prophetic guidance encourages Muslims to purify their speech entirely from such expressions to safeguard their faith and avoid any resemblance to pre-Islamic practices.
Practical Application
When necessary to swear an oath, Muslims should use phrases like "Wallahi" (By Allah) or "Wa'azi-mati-Llah" (By Allah's Majesty). If one accidentally swears by other than Allah, immediate repentance is required.
This teaching trains believers in linguistic purity and constant God-consciousness, ensuring that their speech reflects proper understanding of Allah's uniqueness in worship and sovereignty. The hadith thus serves as both legal guidance and spiritual refinement for the Muslim community.