"Satan is not necessarily opposed to all Christian work. He cares little how zealously we busy ourselves at good things so long as we do not work in the power of the Holy Spirit. He is often pleased if we work so hard and so long that we begin to fret and worry. He is happy if we undertake more work than we can saturate with prayer. He would not seriously oppose if every Christian were a tireless worker -- so long as he worked only in his human energy and was not empowered and anointed by the Spirit of God."
-- Wesley L. Duewel