Authentic Supplication Number 192.

Salem said: 'Ibn `Umar  used to say to the man, if he wanted to go on a journey: come closer to me and let me entrust you [bid you farewell] like the Messenger of Allah  used to entrust us, then he would say: "'Astawdi`ul-laha deenaka wa'amanataka wa khawateemu `amalika (204).

From another perspective, he used to - meaning the Prophet  - when he would entrust someone off, he  take hold of his hand, and not let go of it until the man would be the one to let go of the Prophet 's hand, and he mentioned this.

Footnotes.
(204) I entrust, with Allah, your religion, your trustworthiness, and your closing deeds [meaning your final deeds before death].

Reporters.
Al-Albani said: At-Tirmithi said the first perspective was comely-sound. The second perspective was weakened by At-Tirmithi's statement: A strange hadeeth. A hadeeth is said to be strange when in some of its links there is only one narrator. Al-Albani included this hadeeth in The Authentic of Good Sayings as #135.