اَللَّهُمَّ ثَبِّتْهُ وَاجْعَلْهُ هَادِيًا مَهْدِيًّا

Allaahumma thabbithu waj'alhu haadiyan mahdiyan

O Allah! Make him firm and make him a guiding and a rightly guided man. Narrated by Qais (R): Jarir (RA) said to me, The Prophet (ﷺ) said to me, "Won't you relieve me from Dhu-l-Khalasa?" And that was a house (in Yemem belonging to the tribe of) Khatham called Al-Ka`ba Al Yamaniya. I proceeded with one-hundred and-fifty cavalry from Ahmas (tribe) who were horse riders. I used not to sit firm on horses, so the Prophet (ﷺ) stroke me over my chest till I saw the mark of his fingers over my chest, and then he said: (The dua is mentioned above)

Reference: Bukhari: 4356