His philosophical position was articulated in The Reconstruction of Religious Thought in Islam (1934), a volume based on six lectures delivered at Madras (now Chennai), Hyderabad, and Aligarh in 1928–29. He argued that a rightly focused man should unceasingly generate vitality through interaction with the purposes of the living God. The Prophet Muhammad had returned from his unitary experience of God to let loose on the earth a new type of manhood and a cultural world characterized by the abolition of priesthood and hereditary kingship and by an emphasis on the study of history and nature. The Muslim community in the present age ought, through the exercise of ijtihād—the principle of legal advancement—to devise new social and political institutions.