It is related from ʿAbd Allāh ibn Jaʿfar who said:

“One day the Messenger of Allah, peace and blessings be upon him, had me ride behind him and he confided to me something that I have never conveyed to anyone. He also mentioned that the place he preferred for privacy was a small rise in the ground or a thicket of date-palms. We entered an orchard belonging to a man of the Ansār, and there was a camel inside. When the camel saw the Prophet it groaned and its eyes filled with tears. The Prophet came up to it, stroked its head and the areas behind its ears, and the animal became calm.

He then asked, ‘Whose camel is this?’ A young man of the Ansār stepped forward and said, ‘It is mine, O Messenger of Allah.’ The Messenger of Allah said to him, ‘Will you not fear Allah concerning this beast that Allah has placed in your care? It has complained to me that you keep it hungry and wear it out.’”

Part of this report is recorded by Muslim.