UNTEMPERED (רֵעֶה, H8291). A mixture of lime, whiting and water, for whitening walls, etc. The word is used in the KJV and ASV in Ezekiel 13:10-15; 22:28 (RSV WHITEWASH). The prophet uses it in a metaphorical sense of the false prophets who instead of exposing and denouncing the sinful enterprises of the people weakly acquiesced to them. This is like daubing a stone wall with whitewash to give it the appearance of solidity and strength. A heavy rainstorm will destroy it.
International Standard Bible Encyclopedia (1915)
Used of mortar in Eze 13:10-15; 22:28. Taphel probably refers to mortar made with clay instead of slaked lime. In the interior of Palestine and Syria walls are still commonly built of small stones or mud bricks, and then smeared over with clay mortar. The surface is rubbed smooth and is attractive in appearance. This coating prolongs the life of the wall but requires yearly attention if the wall is to stand.
Ezekiel uses the practice to typify the work of false prophets. They build up stories and make them plausible by an outward semblance to truth, while, in fact, they are flimsy, unreliable prophecies, resembling the walls described above, which can be broken down by a push or a heavy rain storm.
James A. Patch