[...] I am paying an old debt to-day in order to enter upon my new indebtedness to you worthily and in a way to inspire confidence. Please give your wife the accompanying Sonata, my first composition since the completion of Lohengrin (six years ago!). [...]
Source: Letters of Richard Wagner, Vol. 1, selected and ed. Wilhelm Altmann, trans. M. M. Bozman (J. M. Dent & Sons, 1927), No. 245