Dua Bidding Farewell to Someone

When bidding someone farewell. the Prophet (S) would say,
أَسْتَوْدِعُ اللَّهَ دِيْنَكَ وَأَمَانَتَكَ، وَخَوَاتِيْمَ عَمَلِكَ
'Astawdi' laha deenaka wa'amanataka wa khatima amaleek.'
(I entrust to Allah your belief, what you are responsible for, and your final deeds.) (T)