when is lying a mortal sin?

when is lying a mortal sin Exactly or is it always a mortal sin… for example i was looking for something the other day and I was questioned by some man I didnt know about what Exactly I was looking for… I Said “nothing” when I was actually looking for something…now I am a Minor so I didnt have to respond to a strange man at all… I would think this is not mortally or even sinful at all… another example. lets say I have a friend who has developed the habit of stripping while sleeping or to sleep, the point is she developed an embarrassing habit and she still lives with her parents so her father walked in on her while sleeping… she lies to her father right after waking up saying that she was in the process of changing but this was right after she had awaken and her mind was probably not all there yet. last example. Same girl,my friend lets call her amy, amy has fallen into a hole and hurt herself, her children are young and are quite immpresionable she is bleeding and has to go to the emergency room… she tells her children that she is fine and just has to go to the store while she has her friend watch her children. amy leaves her children completely in the dark about the whole accident. Out of these three example which one would count as mortally sinful and which wouldnt. basically when is lying a grave sin… sorry about the wildly drawn out scenarios

CCC 2482 “A lie consists in speaking a falsehood with the intention of deceiving.” The Lord denounces lying as the work of the devil: “You are of your father the devil, . . . there is no truth in him. When he lies, he speaks according to his own nature, for he is a liar and the father of lies.”

CCC 2483 Lying is the most direct offense against the truth. To lie is to speak or act against the truth in order to lead someone into error. By injuring man’s relation to truth and to his neighbor, a lie offends against the fundamental relation of man and of his word to the Lord.

CCC 2484 The gravity of a lie is measured against the nature of the truth it deforms, the circumstances, the intentions of the one who lies, and the harm suffered by its victims. If a lie in itself only constitutes a venial sin, it becomes mortal when it does grave injury to the virtues of justice and charity.

CCC 2485 By its very nature, lying is to be condemned. It is a profanation of speech, whereas the purpose of speech is to communicate known truth to others. The deliberate intention of leading a neighbor into error by saying things contrary to the truth constitutes a failure in justice and charity. The culpability is greater when the intention of deceiving entails the risk of deadly consequences for those who are led astray.

CCC 2486 Since it violates the virtue of truthfulness, a lie does real violence to another. It affects his ability to know, which is a condition of every judgment and decision. It contains the seed of discord and all consequent evils. Lying is destructive of society; it undermines trust among men and tears apart the fabric of social relationships.

CCC 2487 Every offense committed against justice and truth entails the duty of reparation, even if its author has been forgiven. When it is impossible publicly to make reparation for a wrong, it must be made secretly. If someone who has suffered harm cannot be directly compensated, he must be given moral satisfaction in the name of charity. This duty of reparation also concerns offenses against another’s reputation. This reparation, moral and sometimes material, must be evaluated in terms of the extent of the damage inflicted. It obliges in conscience.

thanx for the reply…very helpful

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