Another interesting Diwali legend is of King
Bali. He was a generous ruler but also very ambitious. To
propitiate the gods he performed a Yagna (fire sacrifice). His Yagna
was so successful that even the gods were terrified to appear before
him and grant him a boon in the fear that what he might ask
something which is beyond their capacity. Some of the Gods pleaded
Vishnu to check King Bali's power. Vishnu came to earth in
the form of a dwarf dressed as priest.
When the priest reached King Bali's court, he asked him to ask for
anything he wanted. The priest said "You are the ruler of the
three worlds: the Earth, the world above the skies and the
underworld. Would you give me the space that I could cover with
three strides?" King Bali laughed. This request seemed strange
to all the courtiers, but king Bali granted it. Surely a dwarf could
not cover much ground, thought the King, who agreed to dwarf's
request.
Once the request was granted to him, the priest, who was none but
Visnu in disguise, submerged the entire world (Mrityu-loka) with one
step, with the second he submerged heaven (Swarga-loka) and
for the third step; there was no respectable place to put his foot
down and so he asked the bewildered Bali for some respectable place
to this foot so that the boon could be fulfilled. Left with no
alternative, the noble but exasperated King Bali offered his head
for the purpose. To his surprise, the priest not only lost no time
in placing his foot over King Bali's head, but also thrust Bali into
the nether worlds (Patala-loka) which as per Hindu cosmogony
is hell and lies below the surface of the earth.
The second day of Diwali (Bali Prati-pada) is celebrated in
memory of this. Prati-pada here translates as "below the
opponent's foot" (Prati=opponent, Pada=foot). During Diwali
festival people celebrates the victory of good over evil.
One Diwali story says that Vishnu thrust King Bali into hell. The second day of deepavali is celebrated in this memory.