Invoking Allah Almighty ranks prominently among other worships; rather Prophet Muhammad (PBUH) designed it as worship itself as narrated by At-Tirmithi, ranked Sahih by Al-Albani, on the authority of An-Nu`man ibn Bashir from the prophet commenting on the Quranic verse which reads: (Invoke Me, I shall respond to you (40:60, it appears that the author intended to apply it to Al-Baqarah 2:186). - he said: "The supplication is the worship." And he recited: 'Your Lord said: Invoke Me, I shall respond to you.' up to His saying: 'in humiliation.), surah Ghafir, 60.

Prophet Muhammad (PBUH) has informed us that some times are held more valuable as to the importance of supplication, making day of Arafa the best ever which is demonstrated by At-Tirmidhi, ranked Sahih by Al-Albani, that the Prophet (PBUH) said: (The best of supplication is the supplication of the Day of `Arafah. And the best of what I and the Prophets before me have said is: None has the right to be worshipped but Allah, Alone, without partner, to Him belongs all that exists, and to Him belongs the Praise, and He is powerful over all things. (Lā ilāha illallāh, waḥdahu lā sharīka lahu, lahul-mulku wa lahul-ḥamdu, wa huwa `alā kulli shai’in qadīr).

This is an indication for the importance of Tahlil on the day of Arafa and its importance as a prelude for supplication, thus we should busy ourselves with supplication and Tahlil on the day of Arafa, lest we may not live to another year.

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