Chapter 300
Remembrance 1 from Chapter 300
What to say when one is unable to keep steady on a horse and what supplication is to be made for one
Arabic
Romanisation
Allāhumma thabbit-hu wa-j‘alhu hādiyan mahdiyyā.
Context
WE RELATE IN the Ṣaḥīḥs of al-Bukhārī and Muslim that Jarīr ibn ‘Abdullāh al-Bajalī 
narrated: “I complained to the Prophet 
that I could not keep steady on a horse. He hit me on the chest with his hand and said: ‘O Allah, make him steady and make him a guide who is guided.’” [1].
References
[1] Al-Bukhārī (3036), Muslim (2475).