"Theological and non-theological varieties of utilitarianism agree on the account of the rightness of an action: the rightness depends entirely on the value of the consequences. But there is a difference in respect of the notion of moral duty.
Although our knowledge of God is very limited, we know that he is perfectly benevolent, so there can be no doubt that he desires the maximum happiness for his creatures. We can safely assume that he desires us always to act to promote this end. For us, His desire is a command, and the actions commanded by God are our duties. In this way, theological utilitarians (Paley, Austin) can explain why doing the right thing is a duty. In their view that there can be no duty without a command, they agree with Bentham and many earlier writers on theology and jurisprudence. Bentham's own utilitarianism is non-theological and therefore has no place for the notion of moral duty, but only for the notions of right, wrong, ought, not, and others of that kind."
The Penguin Dictionary of Philosophy
ed. Thomas Mautner
Critique of Brave New World