The Grim Reaper, complete with scythe, first appeared in the Middle Ages and became popular in the 19th century. It’s one of the few phrases drawn from visual art.
Painting time as a concept is very difficult. Once solution is to show the Fates, as depicted by Rubens, Goya, Burne-Jones, Jacek Malczewski and others.
Beards on Father Time, river gods, God the Father, ancient mariners, and lots and lots of artists, especially the Nabis.
Father Time, a grey-haired old man with a beard, wearing ultramarine blue, and holding a scythe and hourglass.
Epitomising human attitudes to life and death for millennia, they spin the thread of life, measure the length allotted to each person, and cut that length with shears.