In one of her loveliest sonnets, never written to be published, Elizabeth Barrett Browning wrote to her husband Robert Browning:
If thou must love me, let it be for naught,
Except for love’s sake only. Do not say,
“I love her for her smile—her looks—her way
Of speaking gently—for a trick of thought
That falls in well with me, and certes brought
A sense of pleasant ease on such a day.”
For these things, in themselves, Beloved, may
Be changed, or change for thee—and love, so wrought,
May be unwrought so. Neither love me for
Thine own dear pity’s wiping my cheeks dry—
A creature might forget to weep, who bore
Thy comfort long, and lose thy love thereby!
But love me for love’s sake, that evermore
Thou may’st love on, through love’s eternity.
From: The Difficult Doctrine of The Love of God, D. A. Carson p. 64 Crossway Books(2000)