17. Wherefore--seeing that ye need to walk so circumspectly, choosing and using the right opportunity of good.
      unwise--a different Greek word from that in Eph 5:15. Translate, "foolish," or "senseless."
      understanding--not merely knowing as a matter of fact (Lu 12:47), but knowing with understanding.
      the will of the Lord--as to how each opportunity is to be used. The Lord's will, ultimately, is our "sanctification" (1Th 4:3); and that "in every thing," meantime, we should "give thanks" (1Th 5:18; compare above, Eph 5:10).

JFB.