Taken from the Telegraph.
Where does the name Easter come from?
Scholars believe the festival to be named after an Anglo Saxon goddess of the radiant dawn, Ēostre, first referred to to in the 7th Century AD. She was associated with joy and blessings.
Only English and German use this name for the festival, with other languages tending towards variations of the Latin “Pascha” or “Passover”. Because of its pagan associations, some christian traditions shy away from using the word Easter, preferring “Resurrection Sunday”.
Why the eggs?
The egg is a symbol of fertility and creation in numerous religious traditions. In Christianity, the egg also symbolises the sealed tomb of Christ. The tradition of decorating these eggs can be traced to early christians in Mesopotamia, who would paint them red to symbolise the shed blood of Christ.
Why the rabbit?
In classical antiquity, writers saw the rabbit (and the hare) as a universally hunted animal that could only survive by its immense fecundity. The rabbit became a symbol of vitality and fertility. In addition, rabbits and hares live underground, promoting associations with the tomb of Christ.
Older Germanic texts mention an Easter Fox or an Easter Stork as bringing the eggs, but these had fallen out of use by the mid-20th Century.
Why is the date always different?
A short answer: Easter is what’s termed a “movable feast”. The death and resurrection of Jesus were originally celebrated after the Jewish Passover and early followers tied the festival to this. The Jewish religious calendar is tied to solar and lunar cycles, which means that the date varies from year to year.