How is "Full Consent" demonstrated since it's a completely subjective experience?


I’m struggling to know what exactly is considered “full consent” of the will in committing a mortal sin.

Since no one can’t know the thoughts and intentions of another, how does one demonstrate what “full consent” is to another?

The Church says in order to commit mortal sin, one has to have “full consent”.

I can’t read the thoughts and intentions of the bishops and popes who declared this dogma.
For all I know, what I consider no consent at all might be considered full consent by the Church.

Basically what I’m asking is, how can I trust my judgement to know something is fully intentional since “intention” is a purely subjective thing that I can only know about myself?


That’s what God and God alone knows.

And when in doubt go to confession on something.


So we should go to confession after every fleeting thought?

I thought we could have moral certainty.


I don’t, because I’m pretty certain when I’ve committed a mortal sin and when I haven’t.

If you can’t tell the difference go to talk to a priest.


It’s not “full consent.” It’s “free consent.” Meaning you engaged your will, chose to do some action, and were not coerced nor moving involuntarily.



For example, a robbery happened. If you agreed to help the robbers in exchange of some of their loot, then you gave your consent. If you are, say, a taxi driver and they hailed you and you didn’t know you’re being an accessory to the crime, that means you didn’t actually commit a mortal sin.


You know and God knows. Nobody else does. That’s why in confession there’s only one accuser: yourself.

And further, the Church always takes the more lenient interpretation. You have it backwards. If you honestly think your consent is less than full and free, then the Church presumes that of you. Neither God nor the Church plays gotcha, and you should drill that into your head.


catechism section 1859:

“Mortal sin requires full knowledge and complete consent. It presupposes knowledge of the sinful character of the act, of its opposition to God’s law. It also implies a consent sufficiently deliberate to be a personal choice.”

Francis’s encyclical Amoris Laetitia has something to say on this as well, esp. the conclusion, chap. 8. It’s online.

If you actually think about this for a while, how free are you? What are the factors that influence your decisions? Genetic makeup, what you have been taught, what is accepted by your friends, what is accepted by your society/culture, the limits of your own knowledge, what you have done in the past, habit…you could go on and on and come up with a very impressive list.

So in light of that, are you able to give “complete consent” to anything? No influences whatsoever pushing you one way or another? Even if you THINK you are making a decision on your own…are you? My personal opinion is that is it virtually impossible to give complete consent to anything–who you marry, career choice, sin, whatever. There is always a lingering doubt–am I doing the right thing? You can’t be immobilized by doubt, so we all make the best decisions we can. But all of them are imperfect–necessarily so since all of our decisions are based on incomplete or imperfect knowledge.

As a side issue you throw in the judgment of other people. No one knows the degree of your consent except God. So no one can judge you. Of course you can be found guilty in a court of law, but that’s a separate issue.

There is a school of thought that the only time you will be completely free is after you die. God will then present you with your sins and you have a choice: in total freedom you can either embrace your sins or reject them. Makes sense to me.


I have never heard this before. It is not what a lot of contributors on this forum believe. Do you have a source?


If in a conversation I say a word that slanders others and it’s only afterwards that I realize it, then there was no full consent when I was fishing, so there is no mortal sin.
Full consent should not be confused with difficulty. If a woman has a spouse who is not her husband but cares for her children, then it will be difficult for her to leave this man. But if she chooses to stay with him there is full consent and therefore there is mortal sin.


My personal criteria is when I hear my conscience telling me “no don’t do it” but I ignore it and commit the sin anyway.


You only need to know about yourself. God knows whether someone gave full consent.


I think in that case, there is rather lack of full knowledge, and not lack of full consent


Not following what you mean?


The way in which I define it to myself is if I know it is wrong but choose to do it anyways I have given full consent and willing committed whatever it is I have willed do to which I know to be wrong.


You may well know that slander is a sin, but in the chatter you can slander without realizing it immediately, but only after!


I have pondered the meaning of “full consent” in the same way the OP seems to be pondering it here.

It is highly subjective as the OP states. A few examples may show the subjectivity of the concept.

If one were to self gratify in a sexual manner; he knows the teaching of the church on the matter and desires in his heart to comply. However in a given moment his urge becomes unmanageable and he fails. Some individuals in these forums (some priests) would say he is guilty of mortal sin, others (including priests) would not (subjective). Those who would not may say the reason why is that the third component of a mortal sin (full consent) is not satisfied while grave matter and full knowledge are.

If one were to contribute to speaking badly of someone in a crowd or party where people are making fun or picking on another. He may have done so reluctantly but could not muster the courage to bow out. He knows it was wrong while doing it but didn’t want to make a seen. Again, grave matter and full knowledge are present that what he is doing is wrong. But his cowardliness compromised his full consent.

It is, as the OP states, subjective. My advice would be, treat it as a serious sin and confess it.

I had a priest once tell me in the confessional (very kindly), “if you committed a mortal sin, you would know it”. The problem I have with this priests statement is, if you use one of the examples I stated above the person would have to say to himself, I understand and agree this actions is of grave matter, but I do not care at all. If that were the case, the person would likely not be an individual who would run to confession following the act. Actually, the person would not likely be one to go to confession at all.


I think that, this case is not concerned by the lack of full consent, but by weakness.


cowardice itself is a sin, so in this case there is a double sin. The default of full consent must not be confused with weakness.


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