Literal meaning.

The length and precision of this proverb leave little room for interpretation as to its meaning. Like many improving mottos, for example ‘a rolling stone gathers no moss’ and ‘a stitch in time saves nine’, it was an encouragement to hard, diligent work. The earliest record of a proverb that approximates to our current version that I can find in print is in The Book of St. Albans, printed in 1486:

As the olde englysshe prouerbe sayth in this wyse. Who soo woll ryse erly shall be holy helthy & zely.