Prayer necessitates servitude, and when prayer was divided into two parts, as we presented, to what is obligatory for notables and what is not obligatory, servitude was divided into two parts: servitude of necessity, with which I pray the obligatory duties of notables, and servitude of choice, with which we pray except for the obligatory duties of notables, and the Almighty God called them voluntary prayers, and the Messenger called them voluntary prayers. God, may God’s prayers and peace be upon him, is voluntary. God Almighty said, “And from the night, perform it as a voluntary prayer for you.” Some righteous people say, “No one has a definite voluntary prayer except for the Messenger of God, may God bless him and grant him peace. For voluntary prayers are not valid except for those whose obligatory duties are complete and those whose obligatory duties are incomplete.