pillars. Basically stones set up on the ground. Many of these sacred stones were used by the Canaanites in their worship. Such pillars were forbidden in Israel’s law (Ex. 23:24; Lev. 26:1; Deut. 12:3; 16:22).
Asherim. See note on v. 15.
under every green tree. Religious activities carried out near certain trees in Old Testament times were considered of special significance (Deut. 12:2; 2 Kin. 17:10; Is. 57:5; Jer. 2:20; Ezek. 6:13; Hos. 4:13).