What is the meaning of "إلا وقف فسأل" (he would only stop and supplicate) mentioned in the Hadith concerning the Prophet's recitation of Surahs Al-Baqarah and Al Imran during the night vigil (Qiyam al-Layl)? Does it mean supplication (du'a), given that supplication is not permissible in Salah except in the Witr prayer?

Abu Dawud narrated a hadith, authenticated by Al-Albani, that permits supplication during recitation in prayer. This is supported by theth hadith narrated by Muslim, in which the Prophet (peace be upon him) recited at a measured pace. When he passed by a verse containing glorification, he glorified (Allah); when he passed by a verse containing a request, he supplicated; and when he passed by a verse containing seeking refuge, he sought refuge. Al-Nawawi held the view that these actions are recommended for every reciter, both inside and outside of prayer, whether for the imam, the follower, or the individual praying alone. Some scholars, such as the Hanafis and Malikis, disagreed, restricting this to supererogatory prayers and not obligatory ones.

Supplication in prayer is not limited to the Qunut. Rather, it has been authentically reported that the Prophet (peace be upon him) supplicated in six places: 1. After the opening takbeer (Takbirat al-Ihram). 2. During standing after bowing (I'tidal). 3. In bowing (Ruku'). 4. In prostration (Sujud), which is the place where he supplicated the most. 5. Between the two prostrations. 6. In the Tashahhud. He also used to supplicate in the Qunut, and during recitation, if he passed by a verse of mercy, he would ask for it, and if he passed by a verse of punishment, he would seek refuge.