This is a classical ,(biblical?) saying. "De teerling is geworpen". I'll try to find what is a 'teerling' ( outdated word ) In this little book with the rules they make a very clear distinction between 'die' and 'dice'.

Edit: Ah, got it:
Julius Ceasar must have said this when he crossed the Rubicon.

Teerling:teerling m. (plural teerlingen, diminutive teerlinkje, diminutive plural teerlinkjes): die, polyhedron used in games of chance