"Cursed is he who does the work of the LORD with slackness, and cursed is he who keeps back his sword from bloodshed"
I do not want to traffic with those who wrench verses from their context. Proof-texting is a curse from which we are still trying to find redemption. I know that this refers to the destroyers of Moab, and the warning is that the sin of Saul in failing to utterly destroy Amelek not be repeated. Those who were to be the Lord's instrument of judgment on Moab were to do His bidding completely (by the way, Justin Taylor has an excellent article titled "How Could God Command Genocide." Read it here)
I had lately read this passage in my morning reading and it came back to my mind at our county fair yesterday. I saw a young lady wearing a tee shirt with this slogan blazoned across the back: "To do anything less than your best is to sacrifice the gift." The author of the quote was on the shirt but I could not read it and didn't want to stare.
This is a great slogan for ministry. What an unbelievable privilege it is to be called and gifted for ministry. If we do less than our best, we sacrifice, nay, we slander the gift that God the Holy Spirit has granted to us. Ministry is not for those who crave a life of wealth, ease, or comfort.