You may wish to skim you way through this FR thread from 2000b'shem Y'shuaThe Seven Festivals Of The Messiah
Interesting. I could go on at length about the parallels between the richness of the Jewish feasts and the Catholic/Orthodox ones.
But instead, let me ask you this...in Leviticus 23 did God give those feasts to the Isrealites or to all the Gentiles?