There is a famous riddle about the dynamics of power in George R. R. Martin's novel A Clash of Kings. Let me post it for the benefit of those who are unaware of it:
“May I leave you with a bit of a riddle, Lord Tyrion?” He did not wait for an answer. “In a room sit three great men, a king, a priest, and a rich man with his gold. Between them stands a sellsword, a little man of common birth and no great mind. Each of the great ones bids him slay the other two. ‘Do it’ says the king, ‘for I am your lawful ruler.’ ‘Do it’ says the priest, ‘for I command you in the names of the gods.’ ‘Do it’ says the rich man, ‘and all this gold shall be yours.’ So tell me—who lives and who dies?” Bowing deeply, the eunuch hurried from the common room on soft slippered feet.
[...]
"Power is a curious thing, my lord. Perchance you have considered the riddle I posed you that day in the inn?"
"It has crossed my mind a time or two," Tyrion admitted. "The king, the priest, the rich man - who lives and who dies? Who will the swordsman obey? It's a riddle without an answer, or rather, too many answers. All depends on the man with the sword."
"And yet he is no one," Varys said. "He has neither crown nor gold nor favor of the gods, only a piece of pointed steel."
"That piece of steel is the power of life and death."
"Just so ... yet if it is the swordsmen who rule us in truth, why do we pretend our kings hold the power? Why should a strong man with a sword ever obey a child king like our own Joffrey, or a wine-sodden oaf like his father?"
"Because these child kings and drunken oafs can call other strong men, with other swords."
"Then these other swordsmen have the true power. Or do they? Whence came their swords? Why do they obey?" Varys smiled. "Some say knowledge is power. Some tell us that all power comes from the gods. Others say it derives from law.
[...]
Tyrion cocked his head sideways. "Did you mean to answer your damned riddle, or only to make my head ache worse?"
Varys smiled. "Here, then. Power resides where men believe it resides. No more and no less."
"So power is a mummer's trick?"
"A shadow on the wall," Varys murmured, "yet shadows can kill. And oft times a very small man can cast a very large shadow."
***
The conclusion is startling, despite being so very obvious:
Power resides where men believe it resides. This applies not just to political power, but power dynamics of other sorts as well. The one which is in my mind at the moment is that of religion: The power of who gets to decide what God ordains.
Imagine a Muslim man in anguish; he has uttered the three baneful words 'Talaq, Talaq, Talaq' (I divorce you, I divorce you, I divorce you) to his wife in a burst of anger. He is now full of regret and seeks council. Before him are three scholars. The first one tells him 'Your marriage is null and void. Leave your wife instantly.' The second one tells him 'Your marriage is intact. You said the words three times together but they will still count as one.' The third one tells him 'Your words are inconsequential. Your marriage was a written pact. It can only be broken in writing.'
Which of these three speaks the law of God? Who decides whether his marriage is valid or not? Just like in the riddle of power, it all depends on the man. Power resides where men believe it resides. The man will decide on whom to confer religious authority... and yet he is just a man, without knowledge of law or revelation.
This becomes acutely relevant when we ponder over the question of reform in religion. Liberal versions of theology are not terribly difficult to come up with in theory. If we consider Islam, there are numerous scholars who have worked out a number of different approaches. Yet, all that work remains academic, with little acceptance and following at large. Religious authority resides where men believe it resides. No attempt at reformation will succeed in practice unless and until men believe it to be true. In this fact lies the practical success or failure of religious reform.
And what controls what men choose to believe?