“Truly wise,” said Abba Iperechios, “is he who teaches, not with words, but with deeds.”
“Another wise Father compares one who teaches only with words, without doing works, with trees which have leaves, but bear no fruit.
“One of the great Fathers of the desert told a certain elder, his neighbor, who always accepted visitors and taught them: “Be careful, brother, for while the oil lamp indeed gives light to many, its wick holder is usually burned.”
Nothing very modern about the concept of being a role model, is there? Seems to be quite ancient. Be what one teaches, do what one teaches.