labor in vain

See: failure
References in classic literature ?
Such will try to discredit the shocking tales of slaveholding cruelty which are recorded in this truthful Narrative; but they will labor in vain.
But for my deep-seated impressions that treasure was here somewhere actually buried, we might have had all our labor in vain.
We pick up the noun in 2:16: "It is by holding fast to the word of life that I can boast on the day of Christ that I did not run in vain [kenon] or labor in vain [kenon].