San Bernardino of Siena (a.k.a. St. Bernadine of Siena) was a great Franciscan preacher from Tuscany who died in 1444. He was very successful at fostering devotion to the Holy Name of Jesus.
The name of Jesus is the glory of preachers, because the shining splendor of that name causes his word to be proclaimed and heard. And how do you think such an immense, sudden and dazzling light of faith came into the world, if not because Jesus was preached? Was it not through the brilliance and sweet savour of this name that God called us into his marvellous light? When we have been enlightened, and in that same light behold the light of heaven, rightly may the apostle Paul say to us: Once you were darkness, but now you are light in the Lord, walk as children of light.
So this name must be proclaimed, that it may shine out and never be suppressed. But it must not be preached by someone with sullied mind or unclean lips, but stored up and poured out from a chosen vessel.
That is why our Lord said of Saint Paul: He is a chosen instrument of mine, the vessel of my choice, to carry my name before the Gentiles and kings and the sons of Israel. In this chosen vessel there was to be a drink more pleasing than earth ever knew, offered to all mankind for a price they could pay, so that they would be drawn to taste of it. Poured into other chosen vessels, it would grow and radiate splendour. For our Lord said: He is to carry my name.
When a fire is lit to clear a field, it burns off all the dry and useless weeds and thorns. When the sun rises and darkness is dispelled, robbers, night-prowlers and burglars hide away. So when Paul’s voice was raised to preach the Gospel to the nations, like a great clap of thunder in the sky, his preaching was a blazing fire carrying all before it. It was the sun rising in full glory. Infidelity was consumed by it, false beliefs fled away, and the truth appeared like a great candle lighting the whole world with its brilliant flame.
By word of mouth, by letters, by miracles and by the example of his own life, Saint Paul bore the name of Jesus wherever he went. He praised the name of Jesus at all times, but never more than when bearing witness to his faith.
Moreover, the Apostle did indeed carry this name before the Gentiles and kings and the sons of Israel as a light to enlighten all nations. And this was his cry wherever he journeyed: The night is passing away, the day is at hand. Let us then cast off the works of darkness and put on the armour of light; let us conduct ourselves honourably as in the day.Paul himself showed forth the burning and shining light set upon a candlestick, everywhere proclaiming Jesus, and him crucified.
And so the Church, the bride of Christ strengthened by his testimony, rejoices with the psalmist, singing: O God, from my youth you have taught me, and I still proclaim your wondrous deeds. The psalmist exhorts her to do this, as he says: Sing to the Lord, and bless his name, proclaim his salvation day after day. And this salvation is Jesus, her savior.
This excerpt from his sermon on the Holy Name of Jesus (Sermo 49, De Glorioso Nomine Iesu Christi, cap. 2: Opera Omnia, 4, 505-506) is used in the Roman Office of Readings for the liturgical memorial of St. Bernadine of Siena on May 20.