Sunan Ibn Majah Book 34, Hadith 1
Messenger of Allah (saas) said: "Whoever does not call upon Allah, He will be angry with him."
"I passed by the Prophet (saas) and he said to me: 'O Hazim, say often: "La hawla wa la quwwata illa billah (there is no power and no strength except with Allah)," for it is one of the treasures of Paradise.'"
the Messenger of Allah (saas) said: "Indeed the supplication is the worship." Then he recited: "And your Lord said: Invoke Me, I will respond to you."