I have asked you before to show where I reject what the Magisterium says. You have up to now failed to do so.
The sole purpose of the Catholic Church is the salvation of souls so I would say that advising sinners not to commit sacrilege is essential to professing the Catholic Faith especially those charged with teaching it: in fact it would be sinful not to advise them of this.
Refusing Holy Communion to a known serial adulterer is a supreme act of mercy. Giving Holy Communion to a known serial adulterer is a mortal sin.