Esther Speaks (spoiler)

He copied this idea from Carl T. Dreyer's Ordet (1955) As many of his scenes in other films they are base in stuff that has been done.

Peace is stronger than love is essentially what's the takeaway from the film. So, it's not love but peace that brings the miracle (if at all it was a miracle that is). Esther used unkind words to describe Marianne previously, so they were obviously at odds with the situation, but the end says they'd gotten at peace with each other to give peace to Johan.

I'd say the film is also open to suggest Esther and Marianne had been in on it along with the community to help Johan attain peace and find what he had really wanted - he wanted everything as it was before, before the affair I'd assume.

Although another poster said that Mr. Reygadas has revealed that Esther's revival was intended to be real, in otherwords a miracle, I'm trying to understand the significance of Johan stopping the clock at the beginning of the film when Marianne has left him to reflect on the "situation," then the frame of the stopped clock half-way through the film just as Johan and Marianne are going away for the day (to reinforce whatever was taking place was not taking place in time), and then the clock being started once again by his father at the end of the film after Marianne is back amongst the living. I am inclined to believe all that happened between the clock stopping and starting again was inner reflection of real and imagined events intertwined with surrealistic elements/metaphors which one oftentimes experiences in deep inner struggle. To me the bottom line of whether events were transpiring in the outer world or inner world, or whether we're asked to believe in a miraculous ending, is secondary to the power and beauty of this production. It really doesn't matter. Acting, cinematography, writing, directing - everything was superb. All in all a wonderfully inspired antidote to the superficial, mind-numbing stuff we have to wade through to find gems like this.