On this day, January 3rd, the Church celebrates the Most Holy Name of Jesus!
The celebration was established eight days after the birth of Christ, when he was circumcised and named Jesus. Despite its origins being as old as Christianity itself, the devotion to the name of Jesus developed primarily from the 12th and 13th centuries onwards. The first references to devotion to the "Holy Name" can be found in the texts of Saint Anselm of Canterbury (1109) and Saint Bernard of Clairvaux (1153).
However, the great "Apostle" of devotion to the Most Holy Name of Jesus is Saint Bernardino of Siena (1444). This Franciscan priest traveled throughout Italy preaching devotion to the name of Jesus, often as a means of reconciling rival families and factions.
Saint Bernardino used to preach holding a tablet with the monogram IHS, formed by the first three letters of the name of Jesus in Greek (Iota-Epsilon-Sigma).
Later, the abbreviation was also interpreted as the Latin acronym "Jesus Hominum Salvator," "Jesus Savior of Men."
There are some variations, but to the trigram (that is, the three letters of the name of Jesus) Saint Bernardino added a cross above the letter epsilon (H), alluding to the Passion, and a sun surrounding the three letters, referring to the Resurrection.
Thus, devotion to the Most Holy Name of Jesus was approved by Pope Martin V (1431) and soon spread. Saint Ignatius of Loyola (1556), founder of the Society of Jesus, adopted the trigram IHS as the emblem of his Order, to which he added the three nails of the Passion. Thus, both Franciscans and Jesuits soon spread devotion to the Name of Jesus.