Matthew 10: 27. What ye hear in the ear, that preach ye upon the housetops.
Public proclamations are still made from the housetops by the governors of country districts in Palestine. Thomson says: “Their proclamations are generally made in the evening, after the people have returned from their labors in the field. The public crier ascends the highest roof at hand, and lifts up his voice in a long-drawn call upon all faithful subjects to give ear and obey. He then proceeds to announce, in a set form, the will of their master, and demand obedience thereto” (The Land and the Book, vol.1, p. 51).
In the contrast expressed between hearing privately and proclaiming publicly, there may also be reference to the mode of instruction in the schools of the rabbis. Lightfoot expresses this opinion, and says: “The doctor whispered, out of the chair, into the ear of the interpreter, and he, with a loud voice, repeated to the whole school that which was spoken in the ear” (Horae Hebraica). He also suggests that the reference to the house-tops may be an allusion to the custom of sounding the synagogue trumpet from the roof to usher in the Sabbath. See note on Matthew 6:22Therefore when thou doest thine alms, do not sound a trumpet before thee, as the hypocrites do in the synagogues and in the streets, that they may have glory of men. Verily I say unto you, They have their reward. (Matthew 6:2) (#643).