O Allah, You are my strength and You are my support. For Your sake, I go forth and for Your sake, I ...
Reference:Abu Dawud 3/42, At-Tirmidhi 5/572. See also Al-Albani, Sahih At-Tirmidhi 3/183.Hisnul Muslim 127
اللّهُـمَّ أَنْتَ عَضُـدي وَأَنْتَ نَصـيري بِكَ أَجـولُ وَبِكَ أَصـولُ وَبِكَ أُقـاتِل
Allāhumma anta `aḍudī, wa anta naṣīrī. bika ajūlu, wa bika aṣūlu, wa bika uqātil.
O Allah, You are my strength and You are my support. For Your sake, I go forth and for Your sake, I advance and for Your sake, I fight.