from the first born] Exodus 4:23. &Exodus 12:29. that is behind the mill] Judges 16:21. Esa. 47. 2. Matthew 24:41. Heb. behind two mills, or after two milstones. The meanest servants (many times) were put to grind at the mill: wherefore mils were often in prison houses, where prisoners and captives were kept in worke, to turne the mill, which was sometimes so made, that they that wrought were placed on the backe part thereof, betwixt the mill it self and the wall of the roome, wherein it was placed: so they were behind the mill, and sometimes they drave it before them, thrusting and turning it about with the maine strength of their bodies, which though it went round, yet still they came behind it, since they forced it about, by driving it before them, rather then by drawing it after them.