When Marcus was sixteen, Hadrian appointed him prefect of festivities in Rome, to take the place of the regular officer, a man of years, who was out of the city. So well did Marcus fill the place and make up his report, that when they again met, the old Emperor kissed his cheek, calling him, "My brave Verissimus," and said, "If I had a son, I would want him just like you."

Playing on the boy's paternal name of Verus, he called him Verissimus, 'the most true." It is interesting to find that this trait of character was so early developed in one who thought that all men "should speak as they think, with an accent of heroic verity."

Instead of calling the boy Marcus Verus, the Emperor gave him the name "Verissimus," which means "the open-eyed truthful one," and this name stuck to Marcus for life. Between Antoninus and Marcus there grew up a very close friendship. Antoninus could scale the ladder up the tall cedar, three rungs at a time, and come down hand over hand without putting his foot on a rest.

The Emperor Hadrian divined the fine character of the lad, whom he used to call not Verus but Verissimus, more Truthful than his own name. He advanced Marcus to equestrian rank when six years of age, and at the age of eight made him a member of the ancient Salian priesthood. The boy's aunt, Annia Galeria Faustina, was married to Antoninus Pius, afterwards emperor.