The Egyptians at first buried their dead without a coffin. By about 4,500 years ago, they were using a plain rectangular coffin. By about 4,000 years ago, they began to paint food offerings and prayers on the coffin, ensuring that the dead could survive in the Afterlife. The anthropoid coffin, introduced about 3,900 years ago, became associated with the mummified god Osiris. The images of gods and prayers painted on the coffin inside and out gave protection to the mummy, the means to survive in the Afterlife and the hope or promise of rebirth and eternal life.