For the King or for the Priests?  

Two monuments to solve a problem 


Niuserre's  sun temple (6th dynasty)

In 5th and 6th dynasty a new phaenomenon occurs: instead of one big pyramid the kings appearently prefer to build not only a pyramid not quite so big as in the 4th dynasty, but at the same time a similar sized sun temple. Some claim this period to be the peak of the Sun worship, but it might as well be a solution to a conflict between the King's interests and the priesthood's.  The pyramid did not just grant the King's glorious afterlife, it also may have functioned as  temple involving rituals, the performance of which gave the priesthoods their importance.

Supposing some rituals were designed to take place inside the pyramid - the holyness of the pyramids can be compared with churches - there would be an inevitable conflict of interests. Should the priesthood be allowed to perform rites in and have access to the deseased king's pyramid, or should it be sealed to grant the king indisturbanned rest?

Cheops’ father behaved rather strangely: he built two pyramids. One was the famous Bent Pyramid, the other one was built a little longer to the north. The mystery: why he suddenly needed two pyramids, is quite fascinating. One logical explanation is that he tried to solve the above mentioned conflict. - You can have Yours, then I want mine for myself! he may have argued.

This off course implies that Cheops deliberately chose to go back to the former solution with one pyramid. The united forces could build the largest pyramid ever, then. 
Following this line other questions become obvious to ask. He must have accepted that the united pyramid was used for ritual purposes, but for how long? We know the ascending passage was sealed with large blocks at a time. This left only the subterranean chamber open for visits - the real burial chamber, as I have argued. 
This seems useless unless the deal was to fill the descending passage as well, or if he accepted rites that dealt with his diseased body, but not any other rites, when he was dead.

He may even have accepted ritual use of the pyramid for some years after his death - until his decessor had his pyramid/temple finished.

Temple for initiations
You may find it too 'new age'-like to talk about initiating rites taking place in the Cheops pyramid. But we do know they took place and played an important role in ancient times. So hold back your disgust and realise that the Cheops pyramid actually was very well suited for the purpose. So was the Bent pyramid.

As early as in 1930 The dane Johannes Hohlenberg [1] described how a possible initiation could take place in the King's chamber. The one who was going through the initiation process had to "die" in the stone sarchophagus, possibly helped by euphorising drugs. Then "the gods" would speak to him. Afterwards he would wake up, remembering that he had been dead and now had come back to life, knowing for certain that the gods existed and had spoken to him. Hohlenberg had no idea that there is an extra chamber, the Sun's chamber, higher in the pyramid. So he figured it all took place in the King's chamber. 

One certain detail expecially supports this theory. High above the floor in the top end of the Grand Gallery a narrow tunnel leads to the lower of the 'construction chambers'. Archaeologists call it an inspection tunnel. But as Hohlenberg thought, a priest could crawl in here and play the role of heavenly voice.

Such cult rites were covered with rules of secrecy, we know from later descriptions from ancient Greek and Roman sources. However, the Roman writer Apulejus has revealed a small part of what happened when he himself was initiated in the Isis cult, and curiously enough he speaks of the elements: 
"...I came to the border of the Land of the Dead...; then I returned, passing through all the elements. In the middle of the night I watched the Sun sparkle with radiance. I stood face to face with the gods of the underworld and the heaven and worshipped them from close range." [2]