...But I keep under my body,
and bring it into subjection:
lest that by any means,
when I have preached to others,
I myself should be a castaway.

1 Corinthians 9:27

How long wilt thou sleep, O, Sluggard?
When wilt thou arise out of thy sleep? 
Yet a little sleep,
a little folding of the hands to sleep:
So shall thy poverty come
as one that travelleth,
and thy want as an armed man.

Proverbs 6:9-11