The works of darkness are unfruitful because they are transient.
And they are unfruitful because, whilst they last, they yield no real satisfaction.
Futile for a time were the parental arguments, unfruitful every effort!
He has not cast out the unfruitful, but has tenderly spared them.
I coughed and made other noises, with like unfruitful result.
Will you be like that ...