Measuring Line (qaw, qeweh): The usual meaning is simply line, rope or cord, in Isaiah 28:10, Isaiah 28:13, but the line was used for measurement, as is evident from such passages as 1 Kings 7:23, Job 38:5, Jeremiah 31:39. Whether the line for measuring had a definite length or not we have no means of knowing. In Isaiah 44:13 it refers to the line used by the carpenter in marking the timber on which he is working, and in Zechariah 1:16 it refers to the builder's line.
Figuratively: It signifies destruction, or a portion of something marked off by line for destruction, as in 2 Kings 21:13; or for judgment, as in Isaiah 28:17.
H. Porter