Traditionally Saint Luke is described as a very cultured man, almost certainly a doctor, with a very precise vocabulary marked by a concern for historical accuracy. He is the author of the Gospel that bears his name as well as the Acts of the Apostles. He was also a theologian who was anxious to emphasise the role of the Holy Spirit in the life of Christ. The Spirit’s important role is affirmed as early at the Annunciation, in the words of the Angel Gabriel to Mary, the future mother of Jesus: “the Holy Spirit will come upon you and the power of the Most High will overshadow you, therefore he who is to be born will be holy and he will be called Son of God”. This same Spirit was also to be at work at the birth of the Church, as described at the beginning of the Acts of the Apostles. Saint Luke is also the evangelist of mercy, with passages that we find only in his writings. He is the only one to describe Christmas, the parable of the Prodigal Son, the Good Samaritan, and the magnificent dialogue on Calvary on the cross between Jesus and the good thief: “Jesus remember me when you come into your kingdom”, and Jesus replies: “Truly I say to you, today you will be with me in paradise”.

The melody of our Gradual chant is called a timbre, that is to say a typical melody which has the ability to adapt to several sacred texts. It can be found in the Wedding Melody (the Gradual Uxor tua) as well as in the Mass for the Dead (the Gradual Requiem æternam). This chant was composed in the 2nd mode. The architecture of this mode is based on the tonic RE and the dominant FA. The subtlety of the composition, conceived several centuries before the appearance of stave notation, required a form of modulation into another modal area: A in the tonic and C in the dominant. The melody emerges from the body of the Gradual, light and alluring, rising from the low register and after a long embroidery around the C, concluding on the A. Notice in the verse the particular emphasis on the words enarrant, gloriam and Dei. The word of the Apostles, which resounded throughout the world, has the effect of releasing divine praise. Caeli enarrant gloriam Dei!