He keeps his word, as the sun keeps butter.
More Dutch Proverbs:
Like will to like, be they poor or rich.Dutch
Love others well, but love thyself the most; give good for good, but not to thine own cost.
Dutch
Who chastises his child will be honoured by him, who chastises him not will be shamed.
Dutch
They agree like cats and dogs.
Dutch
Every flood has its ebb.
Dutch
Give him an inch and he'll take an ell.
Dutch