Ein Mann, ein Wort. — One man, one word. The dictionary DWDS explains: one can rely on what this man announces. It also lists the variant eine Frau, ein Wort. In 2012 Der Spiegel used the phrase about the 89-year-old Henry Kissinger, who kept a promise to visit his hometown football club. In 2017 Die Zeit used it about Olaf Scholz, whose motto had always been Nur das versprechen, was man auch halten kann, promise only what one can keep.