Who said "A grateful heart is the source of all happiness."?

This quote is attributed to Virgil.

A grateful heart is the source of all happiness. - Virgil

"A grateful heart is the source of all happiness."

Virgil Gratitude

Poet Roman 70–19

"I sing of arms and the man who first came forth from Troy's boundaries to Italy and the Lavinian shores."

"Fortune favors the bold."

"What greater thing is there for two human souls than to feel that they are joined for life?"

"I fear the Greeks, even bearing gifts."

"Gratitude makes life richer."

"A grateful heart is a happy heart."

"Respect those who came before us."

"Life's greatest treasures are the people we love"