Honest as the day is long

POP1

So I'm reading Thoureau's journals (July 24, 1852) and I come across the above phrase.  It's too hackneyed a phrase for Thoureau to borrow so I'm guessing that he invented it right here in this paragraph, looking for and finding the perfect expression to describe an honest day's labor.

So I checked on Google and it seems that yes, this is the first time the phrase was used.

But there's more to it.  Thoureau meets his friend Hayden in the morning - 'walking beside his team, which was slowly drawing a heavy hewn stone swung under the axle.'(the axle of a cart I would think). He continues - 'honest, peaceful industry,......A reproach to all sluggards and idlers.'  Then comes a description like something out of an old masters painting - 'pausing abreast the shoulders of his oxen and half turning round, with a flourish of his merciless whip... And I thought, such is the labor which the American Congress exists to protect, - honest, manly toil.   His brow has commenced to sweat.  Honest as the day is long... Toil that makes his bread taste sweet and keeps society sweet.'

POP2

Later that day he sees something that changes his idyllic thoughts.  He sees where the stone was destined.  It's lying beside a whimsical structure intended to adorn a neighbor's yard.  Thoureau sarcastically calls him 'Lord Timothy Dexter' after a well-known American eccentric, and in his eyes the dignity has departed from Hayden's labor because it was subservient to some rich man's foolish enterprise.

Does Thoureau understand that money has to circulate, that the rich man's foolish enterprise is the poor man's daily bread?  The poor man is not working to satisfy the rich man's whim.  He's working for the money.  It's an impartial bridge between the two of them.  The rich man is paying for the work, irrespective of whatever use the poor man puts to the money once it has been earned and received, and the poor man is putting in an honest day's labor.  The poor man is not demeaned by the end result of his labor, nor the rich man by satisfying his  personal whim.  Is there something demeaning in the stonecutter carving the lintel over the rich man's entryway or the master woodworker building him an intricate staircase?