The Shevet Mussar zt”l (in his Sefer Chut Shel Chesed) explains this pasuk by citing the Medrash (Tanchuma Masai 68) that says that Eliyahu Hanavi told the prophets of the ba’al to choose two twin oxen. They brought forth a pair of twin oxen that grew up together, and they drew lots, with one ox picked for Hashem and one picked for the ba’al. The one that drew the lot for Hashem immediately walked towards Eliyahu but the one that drew the lot for the ba’al would not go with them. All of the prophets of the ba’al tried to drag it to their altar but they were unable to move it until Eliyahu told it to go with them.
The ox then opened its mouth and said in front of everybody, “My twin and I were born from the same mother and we grew up together. He is going to be used for Hashem and to sanctify His name. Why should I have to go to the ba’al and to anger Hashem?”
Eliyahu told him, “Go with them and do not feel bad. Just like Hashem’s name will be sanctified with the cow that goes with me, it also will be sanctified by you.”
This explains why the goat that was picked for Azazel had to stand before Hashem. We suspect that because it drew the lot for Azazel, it might not want to go. It might wonder why its peer gets to be offered as a korban to Hashem, while it has to be thrown off a cliff for Azazel. Therefore, we stand it before Hashem to appease it and tell it that it too is making a Kiddush Hashem, as it will serve to silence the prosecutors of Klal Yisroel and bring an abundance of goodness to them.
