Albert Barnes Commentary Zechariah 5:8

"And he said, This is Wickedness: and he cast her down into the midst of the ephah; and he cast the weight of lead upon the mouth thereof." — Zechariah 5:8 (ASV)

And cast her into the midst of the Ephah - The measure, then, was not yet full. Ribera states: “She had the lower part within the Ephah, but the upper part, especially the head, was outside. Though the Jews had killed the prophets and done many grievous things, the greatest sin of all still remained to be done. But when they had crucified Christ and persecuted the Apostles and the Gospel, the measure was full; she was entirely within the Ephah, no part remained outside, so that the measure was filled.”

And he cast the weight of lead upon the mouth thereof - that is, undoubtedly, of the Ephah; as in Genesis, a great stone was on the mouth of the well (Genesis 29:2), so that there would be no access to it.