All now hinges on a letter just promulgated by the leader of the Branch Davidian cult surrounded in his fortress of Mount Carmel. Four pages long and addressed to 'my friends', it purports to be a communication from the Almighty. The document speaks of Koresh himself as 'my servant' and warns that the day of judgement has 'come long nigh'. It is signed 'Yaweh Koresh', a title combining the Old Testament name for God and the Hebrew word for Cyrus, the Persian King who saved the Israelites from the Babylonians.
The language is the standard Koresh brand of pseudo-theology, impenetrable but threatening: according to the FBI Special Agent Bob Ricks, it is 'entirely devoid of Christian references to temperance and non-violence'. The missive is now in Washington, for decoding by Bureau experts in the theology of the last judgement. 'If it's the message from God,' said Mr Ricks, 'we have to know what the heck the message is.'
Pending elucidation, students of the gun-toting Lamb of God are divided. For a dwindling band of optimists, this is It - the revelation which Koresh has been awaiting since the siege began on 28 February. The letter contains six references to the scriptures, among them Jeremiah I, 22-25. 'A sound of battle is in the land, and of great destruction,' the passage reads. 'How is the hammer of the whole earth cut asunder and broken] How is Babylon become a desolation among the nations]'
If this theory is correct, God is telling his disciple that Armageddon will happen during the Branch Davidian Passover, assumed to end on Wednesday. If no cataclysm occurs, then Koresh will know the game is up and agree to answer to earthly justice for his crimes. For others though, the letter is more semi-demented rubbish, not worth the paper it is written on.
Out in the spring countryside deep in the heart of Texas meanwhile, a 43- day exercise in surrealism continues. From two miles away at the press encampment of 'Satellite City', observed through long-distance camera lenses permanently on watch, the ochre-pink buildings of Mount Carmel are a shimmering vision in the heat haze. On the pastureland in between, cattle graze peacefully, oblivious to the helicopters buzzing overhead in preparation for a possible Apocalypse Tomorrow.
The reporters and cameramen themselves seem scarcely more concerned. On Easter Saturday afternoon there was the peculiar sight of a truck carrying huge cylinders of liquid hydrogen passing through a checkpoint. But not an eyebrow was raised. Six weeks of waiting for Godot have taken their toll.
Life for the 90-plus faithful - including 25 Britons - barricaded at Mount Carmel can be scarcely less surreal. Their diet is unleavened bread, spiced by sessions of their leader lecturing on the scriptures. On Friday, the sight of orange smoke issuing from the compound created a stir. It turned out to be merely the ritual burning of incense.
Later that evening Steve Schneider, the mouthpiece of Koresh to a weary world, stepped outside the fortification, only to be chased back inside by FBI 'flash-bang' grenades. Then the searchlights went on once again, turning the cult buildings into an illuminated parody of Jerusalem on an Easter night in the American South. No one knows how long the stand-off will last. The FBI has added to the mystery by placing a ring of barbed wire around the compound. Officially this will help with the 'orderly exiting' of the besieged.
'We still have their attorneys' assurance they'll be leaving sometime this week,' says Mr Ricks. But the wire could equally be a sign of the bureau's belief that this will be a very long haul.