Yes God's command to Abraham to sacrifice his son is what the Eid-Ul-Adha is celebrated for Eid-ul-Adha is also known as the Greater Eid and it is the second most important festival in the Muslim calendar. It is celebrated as a public holiday in Muslim countries. The festival remembers the prophet Ibrahim's willingness to sacrifice his son when God ordered him to. This story is mentioned in the Holy Quran, God provided a momentous ransom at the critical moment when Abraham was about to slay his son. (Surah 37:107)

The same story is mentioned in the Bible (Genesis 22:13). “The fire and wood are here, but where is the lamb for the burnt offering?” Abraham answered, “God himself will provide the lamb for the burnt offering, my son.”(Genesis 22:8). Prophet Abraham took his son Isaac to Mount Moriah where he was to sacrifice him to God. But God sent a lamb instead.

Eid-Ul-Adha is the "Feast of Sacrifice" which is a very important Muslim celebration. It is actually a reminder of the complete obedience and faith in God that Abraham demonstrated when asked to sacrifice his son Ismael. The parallel Biblical story is that of Abraham taking his son Isaac to Mount Moriah to obey the command of God. This difference in the story has been a major dividing point between Muslims and Christians and Jews and some believe that the animosity between the religions is a carry over of the intense jealousy Ismael displayed towards his stepbrother.

According to the Biblical story, Isaac was specifically identified as the son to be sacrificed. Muslims believe that the Quran imiplies that it was Ismael even though his name was not mentioned in this particular passage. Ismael's name is mentioned, however, in the Quran a number of times. According to the Muslim story, God rewarded Abraham with another son (Isaac) for his unwaving faith.

The Bibilical story contends that when Isaac was born, Ismael, then 13 years old mocked and ridiculed the son of Sarah. Sarah demanded that Hagar and Ismael be banished and sent to the desert to fend for themselves. The Quran version is that Abraham took Hagar and Ismael to the desert in response to a command from God when Ismael was an infant.

Abraham was indeed the father of all three major religions, Christianity, Judaism, and Muslim, and God promised Abraham that both Isaac and Ismael would be the father of many nations. Regarding the step brothers, the Bible states that God told Abraham: "Be not displeased because of the lad and because of your slave woman; whatever Sarah says to you, do as she tells you, for through Isaac shall your descendants be named. And I will make a nation of the son of the slave woman also, because he is your offspring." (Genesis 21:12-13 RSV).

Before Ismael was born, Hagar received a message from God regarding her son. "Behold, you are with child, and shall bear a son; you shall call his name Ishmael; because The Lord has given heed to your affliction. He shall be a wild ass of a man, his hand against every man and every man's hand against him; and he shall dwell over against all his kinsmen." (Genesis 16:11-12 RSV)

Isaac was the father of Judaism as his sons became the leaders of the 12 tribes. Ismael was also the father of 12 sons who were the leaders of the Arabs and the land west of Isaac's territory.

The debate continues to this day with scholars from both religious views trying to convince each other that their version is the true and correct story. There are a number of sites that can be accessed on the Internet. Information can be found on any of the sources listed or if you google :"Isaac vs Ismael" you'll receive a list of many more sites.

It has been calculated that in year 1432 (on the Islamic Calendar): November 6th or 7th, 2011 will be the beginning of the celebration this year.