Adam Clarke on Matthew 24:17

Let him which is on the house top - The houses of the Jews, as well as those of the ancient Greeks and Romans, were flat-roofed, and had stairs on the outside, by which persons might ascend and descend without coming into the house. In the eastern walled cities, these flat-roofed houses usually formed continued terraces from one end of the city to the other; which terraces terminated at the gates. He, therefore, who is walking on the house top, let him not come down to take any thing out of his house; but let him instantly pursue his course along the tops of the houses, and escape out at the city gate as fast as he can.

Any thing - Instead of τι, any thing, we should read τα, the things; which reading is supported by all the best MSS., versions, and fathers.