بِاسْمِكَ اللَّهُمَّ أَموتُ وَأحْيَا

In Your name O Allāh, I live and die.

Reference: In Your name O Allāh, I live and die. Abū Dāwud (#5045, 4/311). Also see _Ṣaḥīḥ al-Tirmidhī_ (3/143).