Relations between a human act and the final destiny of a human being. It is the norm of behavior that flows from each person's ultimate end, which is the possession of God in the beatific vision.
Depending on what is conceived to be this final destiny, morality will be determined accordingly. Since Catholic Christianity believes that this destiny is heaven, a human act is either good or bad according as it leads to or detracts a person from his or her heavenly goal. The moral norm of human acts, therefore, consists in their aptitude at leading one to that end. Such an aptitude cannot be created by the human will, nor is it entirely at the disposition of some arbitrary divine freedom. It flows necessarily from the nature of God, from the human nature elevated by grace, and from the nature of the acts themselves. Hence the norm or morality contains precepts that transcend every legislative will. The acts related to them are said to have an intrinsic (essential) morality of good or evil. Extrinsic morality, on the other hand, is external to this built-in relationship between action and purpose; they depend exclusively on the free dictate of the legislator.