Galatians 4:8

When ye knew not God. Paul now apparently addresses himself particularly to the Gentile members of the Galatian churches, and reminds them of their experience before becoming Christians. God had not revealed Himself to them, nor had He given them His law. This did not mean that they had been altogether without any knowledge of God (see Rom. 1:18-21), but God had given a special revelation of Himself to the Jews, who thereby had enjoyed a distinct advantage (see Rom. 3:1,2). God had “winked” at the former comparative ignorance of the Gentiles (Acts 17:30).

Are no gods. They were idols, or false gods, and thus really not gods at all (see 1 Cor. 8:4; cf. ch. 10:20). Before they learned of Christ, the Gentiles had been in bondage to their gods. This was not true of Jewish Christians, for they had not been worshiping idols when they learned of Christ.