In Ezekiel 16:3, Ezekiel tells Jerusalem that her father was an Amorite and her mother was a Hittite. What does this mean? Abraham was not an Amorite, and Sarah was not a Hittite.
Different exegetes have tried to explain this verse. Some focus on the city of Jerusalem, which is, after all, mentioned in the chapter. My HarperCollins Study Bible and Jewish Study Bible both point out that Jerusalem was once a Canaanite city, so Jerusalem was the offspring of Canaanites. My problem with this approach is that it does not really account for other features of the chapter. Ezekiel 16 says that Jerusalem was rejected and forsaken before God decided to raise her as his own and make her beautiful. As far as I know, these things did not happen to the actual city of Jerusalem. When David took it over in 2 Samuel 5 and made it his own city, he did not find it rejected and forsaken. Jebusites liked it enough to live there. Ezekiel 16 probably uses the term "Jerusalem" to mean the entire kingdom of Judah (or the representative of Judah), the same way that prophets use the term "Samaria" for the northern kingdom (see vv 45-46).
Another explanation is that the Amorites and the Hittites preceded the Israelites in the land of Canaan, so they could be called the parents of the Israelites. Maybe, but, again, that does not fit into the theme of Ezekiel 16:1-14: that God found Israel in a pitiful state and chose to love her. The Israelites' bad parents have something to do with that pitiful condition.
The same goes for another popular interpretation, which says that the Israelites were children of the Canaanites in the sense that they imitated Canaanite wickedness. I will call this the spiritual interpretation, since it says that the Israelites were the offspring of the Canaanites in a spiritual, religious, or moral sense. There is some merit to this interpretation, since vv 43-51 condemn Jerusalem's wickedness while calling her the daughter of Canaanites and the sister of Sodom. At the same time, Israel's bad parents cannot relate only to her wickedness in the sixth century B.C.E., when Ezekiel criticized her. In the story that Ezekiel 16 presents, God made Jerusalem beautiful and then she began to decline morally. But, in Ezekiel 16, she was not only the daughter of Canaanites after God made her beautiful. She was the daughter of an Amorite and a Hittite when God first found her in her pitiful condition.
At the moment, the best I can do is to combine the spiritual interpretation with what Ezekiel says about Israel's sojourn in Egypt (prior to the Exodus). According to Ezekiel 20 and 23, Israel was an idolatrous whore even in the land of Egypt. Israel's experience in Egypt resembles what Ezekiel says about Jerusalem in Ezekiel 16: In Egypt, Israel was mistreated, bruised, and despised, until God decided to deliver her and make her his own. When God found Israel in Egypt, Israel was also like an Amorite and a Hittite in terms of her immoral behavior. Still, God showed Israel grace.
Are there any other interpretations that you know?