Palm branches symbolize the triumphal entry into Jerusalem with Jesus riding on a donkey, and the populace cheering him on.
The rooster symbolizes human weakness. Jesus tells Peter, that devoted disciple, "Truly I tell you, this day, this very night, before the cock crows twice, you will deny me three times." And he did.
The Chalice and Cross symbolize the sacrificial nature of Jesus' death.
The most dominant natural phenomena are used
symbolically. The Sun, source of energy and power for the created universe, points
to Jesus as "the Light of the World".
Both Sun and Moon seem to have been wrested from their natural courses when Jesus hung on
the cross, as darkness "came over the whole land" from noon until three in the
afternoon.