Full Idea
Nietzsche was not simply a run-of-the-mill moral relativist. He branded as 'childish' the idea that no morality can be binding because moral valuations are necessarily different among different nations.
Gist of Idea
Nietzsche thought it 'childish' to say morality isn't binding because it varies between cultures
Source
report of Friedrich Nietzsche (The Gay (Joyful) Science [1882], §345) by Philippa Foot - Nietzsche's Immoralism p.146
Book Reference
Foot,Philippa: 'Moral Dilemmas' [OUP 2002], p.146
A Reaction
Relativists about knowledge and morality are inclined to take quotations from Nietzsche out of context. The existence of this database probably exacerbates such intellectual wickedness. Get a feeling for the whole thinker!