Jamieson, Fausset and Brown on Ezekiel 18:6

6. not eaten upon ... mountains--the high places, where altars were reared. A double sin: sacrificing elsewhere than at the temple, where only God sanctioned sacrifice (De 12:13, 14); and this to idols instead of to Jehovah. "Eaten" refers to the feasts which were connected with the sacrifices (see Ex 32:6; De 32:38; Jud 9:27; 1Co 8:4, 10; 10:7).

lifted ... eyes to--namely, in adoration (Psa 121:1). The superstitious are compared to harlots; their eyes go eagerly after spiritual lusts. The righteous man not merely refrains from the act, but from the glance of spiritual lust (Job 31:1; Mt 5:28).

idols of ... Israel--not merely those of the Gentiles, but even those of Israel. The fashions of his countrymen could not lead him astray.

defiled ... neighbour's wife--Not only does he shrink from spiritual, but also from carnal, adultery (compare 1Co 6:18).

neither ... menstruous woman--Leprosy and elephantiasis were said to be the fruit of such a connection [Jerome]. Chastity is to be observed even towards one's own wife (Le 18:19; 20:18).