Full Idea
Kant united the two ideas of virtue (as being and as doing) into the idea of a law that is founded not upon faith but upon reason. Thus in one stroke he united the seemingly irreconcilable philosophical and religious ethics, preserving the best of both.
Gist of Idea
Kant united religion and philosophy, by basing obedience to law on reason instead of faith
Source
comment on Immanuel Kant (Groundwork of the Metaphysic of Morals [1785]) by Richard Taylor - Virtue Ethics: an Introduction Ch.8
Book Reference
Taylor,Richard: 'Virtue Ethics: an Introduction' [Prometheus 2002], p.51
A Reaction
An interesting analysis that sounds exactly right. Taylor's point is that Kant subjects himself to an authority, when the underpinnings of the authority are no longer there. There is a religious strand in the altruistic requirements of utilitarianism too.