The Temple of Luxor was the center of the most important festival of Opet. Built largely by Amenhotep III and Ramesses II, it appears that the temple's purpose was for providing a suitable setting for the rituals of the festival. The Opet festival had a great cosmic significance, it was to reconcile the human aspect of the king with the divine power granted to him by god Amun. During the 18th Dynasty the festival lasted eleven days, but had grown to twenty-seven days by the reign of Ramesses III in the 20th Dynasty.

At that time the festival included the distribution of over 11,000 loaves of bread, 85 cakes and 385 jars of beer. The procession of images of the current royal family began at Karnak and ended at the temple of Luxor. By the late 18th Dynasty, the journey was being made by barges, on the Nile River. Each god or goddess was carried in a separate barge that was towed by smaller boats. Large crowds consisting of soldiers, dancers, musicians and high-ranking officials accompanied the barge by walking along the banks of the river. During the festival the people were allowed to ask favors of the statues of the kings or  the images of the gods that were on the barges.

Once at the temple, the king and his priests entered the back chambers. There, the king and his ka (the divine essence of each king, created at his birth) were merged, the king being transformed into a divine being. The crowd outside, anxiously awaiting the transformed king, would cheer wildly at his re-emergence.

This solidified the ritual and made the king a god. The festival was the backbone of the pharaoh's government. In this way could a usurper or one not of the same bloodline become ruler over Egypt.