Level of consent necessary for mortal sin

[MichaelNZ]

How is 'full consent of the will' with regard to mortal sin defined? I have read somewhere that sufficient reflection is required for a mortal sin. If you do something gravely wrong on the spur of the moment without reflecting on whether you should do it or not, is it a mortal sin?

I was at a job interview this morning, and when asked about my leisure activities I mentioned that I like to read. The guy asked what I was reading at the moment. I have been making my way through The Great Facade by Christopher Ferrara (which is very interesting). However, I said 'not much' as I didn't want to come across as some religious nut. Was this a mortal sin or not?

[Dominicus]

I won't tackle what counts as full consent, I will leave that to one better than I. However I must say I doubt saying "not much" in response to his question was sinful at all and definitely not a mortal sin. It probably wasn't technically even a lie as in your mind you may not be reading "much" if you are only reading one thing. He had no intrinsic right to know what you are reading if you didn't wish to tell him. Secondly, in order for it to be a mortal sin you also need "grave matter" and I doubt this counts as grave matter in anyone's book. You're not going to go to Hell because you didn't tell someone what book you were reading.

You really shouldn't worry about scruples like this, that's the sort of stuff that makes people think you're a religious nut. Its unhealthy and the more you worry over such things the worse your scruples will get. Did you actually think to yourself beforehand "I'm going to commit this particular sin now even though I know with absolute certainty that it greatly offends God" or some variation thereof? If not then its not a mortal sin.