Bismillaahi, tawakkaltu 'alallaahi, wa laa hawla wa laa quwwata ‘ illaa billaah. 

(In the name of Allah, I put my trust in Allah, Whatever Allah wishes will be; there is no strength except from Allah) 

 
[Aboo Dawood, The Book of Good Manners, Hadith 5095; At-Tirmidhee, The Book of Supplication, Hadith 3426]