The thought is the same as in Ezekiel 6:6, but the localities are given in greater detail. The "hills" and "mountains" were naturally the scenes of the worship of the "high places," and these were commonly associated with groves of trees, as in Jeremiah 2:20; Jeremiah 3:6; Isaiah 57:5.
In Hosea 4:13, oaks (or terebinths), poplars, and elms are specifically named (comp. Deuteronomy 12:2; 2 Kings 16:4). Where they did offer sweet savour, etc. The phrase is eminently characteristic of Ezekiel as a priest (Ezekiel 16:19; Ezekiel 20:28, Ezekiel 20:41), and is specially prominent in the books which he must have studied.
It meets us three times in Exodus, seventeen in Leviticus, seventeen in Numbers, and seldom elsewhere. The crowning sin, from the prophet's point of view, was that the incense which was due to Jehovah had been lavished on the false gods of the nations.