BA -
represented the personality, character of individuality of the
dead person - it is shown as a human headed bird. The BA lived
in the tomb but could come and go as it wished, passing undisturbed
through space and time. The BA often visited the land of the
living, here it could assume any form.
KA -
the 'Spirit of Life'. This does not have such a free existance
as the BA - the KA exited the body at death and had to remain
close to the body at all times (the reason for mummification),
and therefore the KA could never leave the confine of the tomb/grave.
However, the KA did still need to have food and drink - offerings
were left (or depicted on walls of the tomb) to sustain the KA.
AKH -
the immortality of the deceased. This spirit was free to leave
the tomb - to become one with the stars - sail in the Solar Boat
of Re - or live with Osiris in the Field of Reeds. But first: