Anas bin Malik narrated that a man said:
"O Messenger of Allah! Shall I tie it and rely(upon Allah), or leave it loose and rely(upon Allah)?" He said: "Tie it and rely(upon Allah)." (ID)
English reference (ID): Vol. 4, Book 11, Hadith 2517 (ID)
Arabic reference (ID): Book 37, Hadith 2707 (ID)