not to the purpose

See: irrelevant
References in classic literature ?
This fair little stranger is so small of bone and sinew, that his old name is not to the purpose.
In pleading, they studiously avoid entering into the merits of the cause; but are loud, violent, and tedious, in dwelling upon all circumstances which are not to the purpose.
How born or bred, and or nourished upon blows and threats on one side, and retorts and defiances on the other, is not to the purpose.
That is true," said the page, "for Senor Governor Sancho utters them at every turn; and though a great many of them are not to the purpose, still they amuse one, and my lady the duchess and the duke praise them highly.
Lord forbidding is pious, but not to the purpose," returned Mr Jaggers.
You are now cool enough, Sophronia, to see that you can't be injured without my being equally injured; and that therefore the mere word is not to the purpose.
But this is not to the purpose, -- our business concerns Valentine, let us leave the dead in peace.