It is inconsistent to use “moral gravity” to specify degrees of immorality. However, my Church uses a concept of moral gravity to mark out some acts as morally grave. If the “matter of the act” – what the act is- is morally grave and done with full consent of the will after sufficient reflection the act is a mortal sin. For the Church, “morally grave” has the negative connotation of morally wrong. I intend to follow the Catholic Church’s usage.

(Added Sept. 1, 2022: Perhaps I should not write of “morally grave matter” but write simply “grave matter. For when I transition from command moral theory to divine command moral theory, I should allow for direct commands of God to do more than what is morally required. But I do not need to allow for the prospect of the divine moral commanded directly commanding an act contrary to morality. For in development of this moral theory we move up from being a moral commander to being a divine moral commander.)

The question remaining for me is, “What do I intend to say about acts when I follow the Church in labelling them “grave matters?” I am developing an intension -definition- to cover the extension picked out by the Church’s use of “grave matter.”

Here is how the Church specifies “grave matter” in the Catechism of the Catholic Church.

1858 Grave matter is specified by the Ten Commandments, corresponding to the answer of Jesus to the rich young man: “Do not kill, Do not commit adultery, Do not steal, Do not bear false witness, Do not defraud, Honor your father and your mother.”132 The gravity of sins is more or less great: murder is graver than theft. One must also take into account who is wronged: violence against parents is in itself graver than violence against a stranger.

For one, I intend to use it with the negative connotation of being wrong. To say that a type of act is a grave matter is to say that it ought not be done.

But of most importance, I intend to use it as a moral concept in command moral theory and then as a religious morality concept in divine command moral theory. Because I intend to use the concept of “grave moral matter” in divine command moral thinking, I wrote of grave matter as generally “something which ought not be done” instead of as specifically “something which ought not morally be done.”

There are no degrees of immorality. But there can be degrees of the disobedience in the disobeying of a moral command. Disobeying a moral command places an agent in confrontation with the moral commander. This confrontation need not be total confrontation which puts the agent at enmity with the moral commander.

So, I propose to use “moral gravity” to measure the degree of disobedience in disobeying a moral command. An act is a grave moral matter if its performance is the highest degree of disobedience to the moral commander.

There is a critical point in the gravity of acts at which they become grave. Below this point grievousness is not grave. At this critical point acts are grave. Above this critical point acts become more and more grave.

How might we decide that an act is a grave matter? If we stay at the level of command moral theory, brevity of the argument to show that the act violates a moral command might measure degree of disobedience. Acts whose wrongness is almost axiomatic would be grave matters. If we move to religious command theory, resources of the religion such as scriptures, tradition and teaching authority are available to specify what comes directly from the religious moral commander.

Note, though, neither the intentions of the agent, the circumstances of the act and consequences of the act are used to determine its gravity. The gravity of an act, thus, seems similar to intrinsic immorality of acts. Gravity, though, is a concept of a relation between the act and the moral commander; thus, not only about features intrinsic to the act. Independently of the performance of an act, there is a degree of command relation between the moral commander and the act. There is a varying degree of directness of command. That relation prior to performance is measured by moral gravity. There is a declining scale of directness of command by the moral authority of immoral acts.

For instance, Killing someone is directly forbidden by the Fifth Commandment. But punching someone in the face is only a distant implication of this commandment.

Call the performance of an act an “action.” The sinfulness of an action is not an intrinsic feature of the act performed. Sinfulness is a relation between the agent of an action and the moral commander. Sinfulness comes in degrees and it depends upon the intention of the agent and the agent’s circumstances as well as what is done, viz., the matter of the action.