Taken that a good friend would give you advices to abstain from things which could harm you or of bad results, what advices would you give, being in such a possition, knowing that cause and effect isn't a democratical thing, or a "liberal"? Would you send him in an easy fatal lost "war" to win his favor, give into possible defilements?
While it is a very seldom gift of being well-wished adviced, even if disliking, think on you as a child and your parents, it's not something you are obligated to and so worthy to think clear why wishing to do, honest.
Just a sample, not to present something, but to have a possibility to think maybe more from outside, as life actually runs different as thought, as just one to give: Assimilating of Bhante Samahita's death, decay of beloved
For on ordinaty person it's really hard to keep preoccupations, feeling... seperated, not to speek of understanding of what possible just known from far.
So it's really not an easy issue if serious wishing to build up Nissay with those headed toward liberation, not even if after good, firm, intellectual understanding.
May all take care and often remember their parents hardship to even letting have grown till here.
For all that reason, since the old, people are adviced to focus their dedications toward the Sangha and others then the most think, the Buddha gave also to householders advices of how to react on "troublesome" monks, since thinks aren't for sure! And the Buddha knew his Pappenheimer:
...Anāthapiṇḍika the householder heard that, “They say that the Kosambī monks, quarrelsome, makers of strife, makers of disputes, makers of rumors, makers of issues in the Saṅgha, are coming to Sāvatthī.”
Then Anāthapiṇḍika the householder went to the Blessed One and, on arrival, having bowed down to him, sat to one side. As he was sitting there, he said to the Blessed One, “Lord, they say that the Kosambī monks, quarrelsome, makers of strife, makers of disputes, makers of rumors, makers of issues in the Saṅgha, are coming to Sāvatthī. How am I to behave with regard to these monks?”...The Discussion of the Eighteen Grounds
Old lay people in tradition countries, wouldn't advice or support one, nearly generally, especially if having been monks, but of course they had no google and suttacentral-monks, which might be useful or will most eternal cut of the stream of those rest heading already outward. So again, right critic leads to heaven (even if just by ones thought) and wrong likewise to hell. So the proverbs of binding a knot into your tongue aren't out of reason, one can be sure, and for good deeds one does not need to become a "killer", not even one who stuggles outwardly long. In both directions, and the rest stays open for real compassion and seldom left paramis one could have.
And to add an importand issue, kamma, and that's what the most here is about, doesn't care whether you then tell wrong just your friend, spread it cicretly or anonymuosely... a larg bypass downstairs as well, by especially "smart".
There should be no issue better to simply direct the case direct, and if no "success", onecan deside to left another off for one self, not even just at least.
(Note that this isn't given for trade, exchange, stacks or what ever binds, but for freedom from it.)
