Aker embraces the world - he is represented as the sign of the horizon in-between two lions (sometimes these may be human forms instead) which are seated back to back (one animal faces west - where the sun sets each day and begins its journey into the night and Underworld, the other lion faces the east where the sun rises each morning free once more from the realm of darkness).

Aker guarding the entrance and the exit to the Underworld.

Ancient Egyptian mythologists believed that during the night the sun journeyed through a tunnel that existed in the earth - its entry into the tunnel caused the night, its emergence again bringing the day once more. Each end of this tunnel was guarded by a lion god, and the two gods were called Akeru (also known as Akherui):

 Frist mention of Aker

Aker is an old god from ancient Egypt - he is first mentioned in the Pyramid Texts, and from the passages in which his name occurs is thought that he had a very clear and well defined role in the Early Egyptian kingdoms.

'Yesterday' and 'Today'

In the later period of Egyptian theology the two lions making up the Akeru were named Sef and Tuau - 'yesterday' and 'today' respectively.

Aker in the Egyptian home

Because the ancient Egyptians believed that Aker guarded the gates of the morning and night, statues of the lion god were placed at the doors of houses and also at tombs to guard both the living and the dead from evil spirits and more eartherly foes. These lion guardians were sometimes given the heads of men and women which turned them into a more recognisable form - that of the Sphinx.