Proverbs 13:11 He That Gathereth By Labour Shall Increase
Proverbs 13:11 (KJV) Wealth gotten by vanity shall be diminished: but he that gathereth by labour shall increase.
Labour is profitable. Hard work shall be rewarded
It is contrasted with wealth gotten by vanity. Without honest labour, wealth will not be kept by the owner. It slips away.
As the psalmist well explained in Psalm 128:2 (KJV) For thou shalt eat the labour of thine hands: happy shalt thou be, and it shall be well with thee. Amen.