Only God can perform miracles. Humans are not able to suspend the rules of nature and interrupt the chain of causality.
For the flamers: God can listen to someone’s prayers and perform a miracle. Canonization is based on, among other things, someone having interceded with God for the performance of a miracle.
“Only God can perform miracles”
Absolutely true, but sometimes God DOES use human agents, sometimes angels and sometimes He acts Himself.
A finite mind can’t comprehend an infinite God.
God can work through people.
Ever hear of an exorcist?