“I was with Abu-Bakr Ibn Mujahid when Hadrat Shibli came. Abu Bakr Ibn Mujahid stood for him(welcomed him) and embraced Hadrat Shibli and kissed him between his eyes. I said to him: “O my Master! Are you doing this to Shibli and you and everyone in Baghdad think of him as a madman.”
He said to me: “I treated him the way I saw Messenger of Allah (sallAllaho alaihi wa ala alihi wa sallam) do and that is, I saw Beloved Prophet(SallaAllaho alaihi wa ala alihi wa sallam) in my dream and he welcomed Shibli, he stood for him and kissed him between his eyes. I asked : “Ya RasulAllah (sallAllaho alaihi wa ala alihi wa sallam), are you treating him like this(People consider him a madman!)?” Prophet (sallAllaho alaihi wa ala alihi wa sallam) answered: “He recites after every prayer, لقد جاءكم until the end of the Surah (Surah Taubah, Verses 128-129).”
In one narration, it is cited that after every obligatory prayer he recites لقد جاءكم until the end of Surah and then recites three times: صلى الله عليك يا محمد
He (Abu bakr) said: When Hadrat Shibli visited him, I asked him about what he recites after every prayer and he mentioned like this.
-Ibn Qayyim (Jala’ul Afham fi Fadli’ Salat Wasalam Ala Muhammad Khairal Anaam,pg 329)
The Master of Both Worlds SallAllahu Alaihi wa Sallam said,
أولى الناس بى يوم القيامة أكثرهم على صلاة
The closest to me on the Day of Judgement will be the one who recited the most Durūd upon me in the duniyah.
The blessed Companion Ubay bin Ka'ab said that, [aside from my Fardh obligations, etc.] I will devote all my time in reciting Durūd. Upon this, the Master of Madīnah al-Munawwarah SallAllaho Alaihi wa Sallam said to him,
إذا تكفى همك ويغفر لك ذنبك
This will be sufficient to drive away your worries and shall be redemption for your sins.
Sayyiduna Abul Qasim Qushayri Radi Allahu Ta'ala Anhu narrates that Allah Almighty sent a revelation to Sayyiduna Musa Alaihis Salam saying, “I created 10,000 ears in you by which you heard my speech and 10,000 tongues by which you spoke to me. You will become beloved to me when you send Durud upon Muhammad SallAllaho Alaihi wa Aalihi wa Sallam.”
ar-Risalat al-Qushairiyyah, Dar al-Kutub al-Ilmiyyah - Beirut, Page 377