SAND (ἄμμος).—Sand, which, however closely packed and hard, seems almost to melt at the touch of water, is a foundation on which only a fool would build (Matthew 7:26). St. Luke in the parallel passage gives ἐπὶ τὴν γῆν, ‘on the earth’ (6:49). The surface of the earth, baked hard in the heat, goes swiftly to soft mud when the rains come.
W. Ewing.