According to the Roman Catholic church, there are mortal sins and venial sins.
The Bible, however, knows nothing of this, and only refers to sin, and as the, 'wages of sin is death,' then all sin is, 'mortal.'
Also, the Bible tells us that ALL have sinned, which is why we are in need of a Saviour, Jesus Christ, to save us from the consequences of our sin.
There is no distinction. A sin is a sin is a sin.
Even those who commit sins considered mortal, by those who like to be clear about their rules & regs (murder etc, basically anything in the 10 Commandments) then they can still show remorse, repent their sins and receive atonement (e.g. Constantine). Dieing in mortal sin generally means that you have never sought to redeem yourself of your sins before dieing; I doubt the Pope knows anyone like that at a personal level.
You're quite right, naomi, and welcome back, by the way.
Much RC dogma is invented and has no basis in scripture. Examples:
That contraception is a sin.
That Mary was also born of a virgin (called Anna).
That Mary remained a virgin all her life.
That the brothers and sisters of Jesus were cousins or children of an earlier Joseph marriage.
That Peter became the first bishop of Rome.
That the bread and wine at the Eucharist ( a pagan ritual, incidentally) actually turn into the body and blood of Jesus in the stomach. Ugh!
I'm sure there are others which escape me for the moment, but there are enough there to prove your point.
Sin is purely a religious concept which needn't concern the rest of us.