When I was in Roman Catholic RCIA classes, our class was informed that missing communion out of laziness or without prior approval from your parish priest was a mortal sin.On the whole "does it damn Catholics to not receive communion" issue, there are plenty of practising Catholics who don't and can't receive. Who are they? Those who are divorced and remarried. At no stage have I ever heard the Catholic Church call their salvation into question because of that.
From an Orthodox Church perspective, it's up to me when and if I should abstain from the chalice...meaning if I haven't properly prepared myself for communion, I should abstain. I know some Orthodox Christians that take communion only on major feast days or only on Pascha. BUT, for example, if an Orthodox Christian is separated from his or her spouse or is divorced, they will not be allowed to approach the chalice for communion until the priest sees fit.
So from a RCC perspective, I'm sure if the parish priest tells a practicing Catholic to abstain from the elements (for whatever reason), their salvation isn't in jeopardy...but it seems to me from my RCIA class if you willfully abstain then it is a mortal sin, until he/she confesses...maybe I should've asked more questions, but didn't.
In XC
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