Faith can be a very powerful thing.
If you believe something is going to happen, it becomes more likely that it will - even if your belief has no concrete foundation.
This is apparent in the placebo effect, which means sugar pills and saltwater injections have been clinically proven to alleviate symptoms of illness, simply because the people taking them believe in them.
Faith works. Just look at the extraordinary tale of Tim Tebow, a devoutly-Christian NFL quarterback whose apparent lack of basic skills have proved no match for an iron conviction that he will win.
The wildly unorthodox Tebow took the Denver Broncos on an extraordinary winning run into the playoffs, and became one of the most celebrated sportsmen in America.
Tebow's team-mates and fans believe in him absolutely, and that - to a point - is enough to overcome obvious, gaping flaws in his skill set.
In football, then, there is nothing wrong with a manager whose main asset is the faith and devotion he inspires.
However, it is imperative that such a person does nothing to make his players and fans question their faith in him.
We saw at the Emirates Stadium on Sunday the corrosive effect of a previously revered manager losing his grip, and causing the faithful openly to question his decisions.
The furious reaction of the fans, and of Arsenal captain Robin van Persie, to Arsene Wenger's substitution of Andrei Arshavin for Alex Oxlade-Chamberlain, would have been unthinkable even two years ago when it was assumed Wenger had the job for as long as he wanted it.
Wenger may ride out this present storm of discontent, but it is clear that things will never be the same again for the Frenchman.
Which brings us to Kenny Dalglish, a man held in reverence by Liverpool fans and players alike. Whose return to Anfield was greeted with unbridled jubilation.
Dalglish has a huge amount of credit in the bank with Liverpool fans, and understandably so.
Not only is he arguably the greatest player in the club's history, and the architect of three league titles as manager.
More than anything, he personifies the glory of Liverpool Football Club.
There is a palpable sense that Dalglish 'gets it'. He knows what matters to supporters, and he is more interested in protecting the institution he loves than spinning a handy PR line.
Although that philosophy led to his lamentable handling of the Luis Suarez case, it is hardly surprising the fans admire his love for the club.
He has an umbilical link to those fans, and no manager in the Premier League owes his position to them like Dalglish.
That is why he was so upset with the performance in defeat against Bolton on Saturday.
For the first time under his management, Liverpool appeared devoid of spirit, commitment and pride - intolerable.
Dalglish said: "If it is going to be repeated then there will not be too many repeating their appearances in a red shirt because we won't stand for that.
"Respect is a huge part of being a successful club and if they do not have that respect for other teams and, most importantly, this club, they are in a bit of trouble."
Not only are they in trouble - Dalglish is in trouble. If he can no longer inspire 100 per cent commitment from his charges, then he is nothing.
Dalglish oozes passion, but he is not a great tactician, nor is his eye for talent as sharp as, say, the impassive, detached Roy Hodgson.
If his passion loses its impact, Dalglish has had it.
Which is why last night's triumph against Manchester City, at an electric Anfield, was so important.
A few questions were starting to be asked about King Kenny. The Suarez affair was a horrible moment for the club, his big money signings were failing to perform, and - unthinkably - the team could not win at home.
None of those problems have gone away (yesterday's result was the seventh draw in 10 home games), but we are dealing with faith, not facts.
Not only did last night showcase a Liverpool side brimming with their manager's zeal, it gave a much-needed reminder of what glory feels like, and renewed the belief that this glory will be attained under Dalglish.
Yes, it's only the Carling Cup. But do you think that will matter to any of the fans travelling to London for Liverpool's first match at the new Wembley?
In any case, the faithful are convinced that this is only the start of the success under Dalglish.
If their belief holds firm, they might just turn out to be right.