During the morning puja, or
worship, the Deity or a salagrama is bathed in pure ghee. Srila
Prabhupada once explained the festival this way: "Krishna was just
a toy in the hands of the Gopis, so one day the Gopis decided that
we shall decorate Him. Pusya abhisheka means a ceremony to decorate
the deity profusely with flowers, ornaments, cloths. After there
should be lavish feasting and a procession through the streets, so
that all the citizens should see how beautiful Krishna
appears.
(Krsna-priya Devi Dasi, Vaisnava
Academy - Alachua)