What is the significance of looking to the north?
Rashi: It is to Har ha'Bayis, outside the Azarah, for he was standing in the north gate of the Azarah. North of this gate is outside the Azarah.
Radak: In the north gate they built a Mizbe'ach to Semel ha'Kin'ah. Therefore, it is called "Sha'ar ha'Mizbe'ach."
Radak (14): This was a hint that "mi'Tzafon Tipasach ha'Ra'ah" (Yirmeyah 1:14).
What is "Sha'ar ha'Mizbe'ach"?
Rashi: It is the north gate of the Azarah. I say that it was opposite the Mizbe'ach 1 .
Radak: Refer to 8:5:1:2.
What is "ba'Bi'ah"?
Rashi: When one comes to enter the Azarah, he finds [Yechezkel] there.
Malbim: They put "Semel ha'Kin'ah" by the opening, lest [the power that does evil] enter to destroy them. The Korbanos were so he would distance from them, and not do evil!