You do have to be very careful, I agree. There are charlatans all about us. The Church, however, does the work for us, in determining whether one should be canonized. And it would be counter-productive of the devil, regardless, to allow the types [and number] of miracles that came about through the intercession of St. Gemma Galgani.
...”The Church does the work for us”.....
Jesus says in 1 Corinthians 3:1-4
But I could not address YOU as spiritual people, but as people of the flesh, as infants in Christ. I fed you with milk, not solid food, for ‘you were not ready’ for it. And even now you are not yet ready, for you are still of the flesh....For when one says, “I follow Paul,” and another, “I follow Apollos,”.. are you not being merely human?.......
....For who has understood the mind of the Lord so as to instruct him?”.... But we have the mind of Christ.....
therefore...
Be transformed by the renewal of your mind, that by testing YOU may discern what is the will of God, what is good and acceptable and perfect........ICor.2;16..Romans 12;2
Over and over in Scripture, we hear the saying that “the Word of the Lord” came to Ezekiel, Jeremiah, and the other prophets....It is very rare it says the Spirit came....... God revealed himself to the prophets ‘by His Word’. Yet the Word and the Spirit are synonomous, they work ‘together’.
Jesus engaged the whole person, especially the mind. He answered the questions of the people giving them answers not avoiding them.... Nowhere did he tell them not to think for themselves. In fact he gave long sermons teaching them, enaging their minds.
I can save 'the church' a LOT of 'work'.
'Canonize' NO one. It is not doing a thing except wasting time.