I have several questions regarding impure thoughts. Can they be mortal sins? How should I confess them? Do I need to go into detail?
These are very commonly asked questions, and it is good that I have the opportunity to answer them, both for you and for many others.
First of all, what do we mean by impure thoughts? We mean thoughts of actions or situations which if acted upon by the particular person would involve committing a sin against chastity.
Thus the thought a young man has of going to bed with a young woman would be an impure thought, whereas the thought a married man has of going to bed with his wife would not be.
But if the married man had thoughts of going to bed with some other woman they would be impure thoughts.
In the genesis of impure thoughts one can distinguish several stages, which are helpful in judging their morality.
In a first stage the thoughts simply appear in the imagination without being sought. The fact that they are in the mind does mean that the person has sinned.
The thoughts at this stage are not voluntary, they have just appeared, and there can be no sin until the person consents to them.
But there may have been prior sins that led to the thoughts.
For example, if someone has watched an unchaste film on television the night before, or has looked at pornography on the internet, that in itself is putting oneself in an occasion of sin without good reason, and is therefore sinful.
In this sense, the person is responsible in some measure for the present impure thoughts, even though the thoughts in themselves are not yet sinful.
In a second stage the person becomes aware that he or she is having thoughts which are impure.
At this moment the possibility of sin enters, because the will can now reject the thoughts or consent to them.
If the person consents to them and continues dwelling on them voluntarily, there is certainly sin.
Will it be venial or mortal? If the person takes great pleasure in the thoughts, imagines in some detail committing an impure act, prolongs the thoughts for some time, “fantasises” in the imagination, often experiencing bodily pleasure, the sin will most likely be mortal.
Jesus alluded to this when he said, “But I say to you that every one who looks at a woman lustfully has already committed adultery with her in his heart” (Mt 5:28).
It is not merely looking at a woman that is sinful, but the lustful thoughts in the mind, the impure desires, that constitute the sin.
And it is clear from Jesus’ words about committing adultery in the heart, that the sin is mortal.
If, however, on adverting to the impure thoughts the person recognises their immorality and rejects them, there will be no sin.
It can be helpful in these situations to imagine Jesus suffering excruciating pain in the scourging at the pillar or on the cross, as an incentive to avoid offending him by seeking illicit pleasure.
Likewise, it can be helpful to pray to Our Lady, “Mother most pure”, “Mother most chaste”, in order to obtain the graces necessary to reject the temptation.
And always, it is important to distract the imagination from the impure thoughts by thinking about anything that truly engages the mind and is not sinful.
For example, thinking about one’s work, one’s recreation, one’s plans for the weekend, etc.
If the person struggles with determination to reject the thoughts, he or she will actually grow in sanctity and acquire great supernatural merit through the struggle.
The person has been tested and found worthy, and God will reward them for their fidelity.
If the person recognises that, even though they are trying to reject the thoughts, they have given in to some extent, there will be venial sin but certainly not mortal sin.
How should these thoughts be confessed? It is not good to say “I have had impure thoughts”, since the thoughts in themselves are not sinful.
The person should give some indication as regards the extent to which they think they have consented to the thoughts.
And if the thoughts have involved particular persons in special relationships, for example impure thoughts towards a family member, towards a person dedicated to God in a vocation to celibacy, towards someone of the same sex, towards someone other than one’s spouse, etc., this aggravating circumstance should be mentioned.