Unclean vs Common

Act 10:11-15 MKJV
(11) And he saw the heaven opened and a certain vessel like a sheet coming down to him, being bound at the four corners and let down to the earth;
(12) in which were all the four-footed animals of the earth, and the wild beasts, and the reptiles, and the birds of the heaven.
(13) And a voice came to him, saying, Rise, Peter! Kill and eat!
(14) But Peter said, Not so, Lord, for I have never eaten anything that is common or unclean.
(15) And the voice spoke to him again the second time, What God has made clean, you do not call common.

This is a confusing passage. God is teaching Peter a lesson about love and avoiding prejudice. The Torah is very specific about clean versus unclean (Greek akathartos), but what exactly is 'common' (Greek koinos)?

That which was unclean in a Levitical sense was to be abstained from; avoided altogether. Lepers were unclean. Those things which were common were things 'unhallowed' or ordinary. To the Jewish mind of that period, anything 'heathen' or Gentile was common, but not necessarily unclean.

God is telling Peter not to call cleansed things common. He is not saying that He has cleansed unclean things. The disconnect was that the Jews had placed Gentiles in the common category, despite the fact that the Torah never classified Gentiles as either unclean or common. In fact, Paul wrote "there is nothing common of itself" (Rom 14:14). Torah specifically says:

Lev 19:34 MKJV
(34) The stranger that dwells with you shall be to you as one born among you, and you shall love him as yourself. For you were strangers in the land of Egypt. I am Jehovah your God.

The Jews relied on an oral law - one passed along from generation to generation. This was not written down and many had their own 'takes' on this law. Peter said this:
Act 10:28 MKJV
(28) And he said to them, You know that it is an unlawful thing for a man, a Jew to keep company with or to come near to one of another nation. But God has shown me not to call any man common or unclean.

By 'unlawful', Peter referred to the oral law, as Torah said no such thing. The mingling of seeds was forbidden according to Torah, and so was the mixing of nations (intermarriage with heathen nations), as Israel was a Holy Nation. Oral law, however, took this further than God did.

Act 10:34-35 MKJV
(34) Then Peter opened his mouth and said, Truly I see that God is no respecter of persons;
(35) but in every nation he who fears Him and works righteousness is accepted with Him.