The beginnings of the veneration of the Most Holy Name of Jesus date back to the liturgical celebrations of the 14th century. St. Bernardine of Siena in the 15th century, along with his disciples, spread the veneration of the name of Jesus and a century later, around 1530, Pope Clement VII granted the Franciscan order authorization for the celebration of the Office of the Holy Name of Jesus.
IHS
St. Bernardine used to carry a wooden placard showing the Eucharist surrounded by rays with the monogram “IHS,” an abbreviation of the name of Jesus in Greek (Ἰησοῦς).
Later, the devotional tradition added a new meaning to this monogram, turning it into a Latin “Christogram”: “I” for “Iesus” (Jesus); “H” for “Hominum” (of men); “S” for “Salvator” (Savior). That is, IHS means “Jesus, savior of men.” New meanings would be added later.
St. Ignatius of Loyola and the Jesuits made this monogram the emblem of the Society of Jesus.