93. Each gospel reading has a distinctive theme: the Lord’s coming at the end of time (First Sunday of Advent), John the Baptist (Second and Third Sunday), and the events that prepared immediately for the Lord’s birth (Fourth Sunday).
The Old Testament readings are prophecies about the Messiah and the Messianic age, especially from the Isaiah.
The readings from an apostle serve as exhortations and as proclamations, in keeping with the different themes of Advent.
94. There are two series of readings: one to be used from the beginning of Advent until 16 December; the other from 17 to 24 December.
In the first part of Advent there are readings from Isaiah, distributed in accord with the sequence of the book itself and including salient texts that are also read on the Sundays. For the choice of the weekday gospel the first reading has been taken into consideration.
On Thursday of the second week the readings from the gospel concerning John the Baptist begin. The first reading is either a continuation of Isaiah or a text chosen in view of the Gospel.
In the last week before Christmas the events that immediately prepared for the Lord’s birth are presented from Matthew (chapter 1) and Luke (chapter 1). The texts in the first reading, chosen in view of the Gospel reading, are from different Old Testament books and include important Messianic prophecies.
A more general guide to the season of Advent can be found at http://www.liturgyoffice.org.uk/Calendar/Seasons/Advent.pdf
The readings of the first Sunday of Advent, then, turn us to the end times, to the end of earthly history, to the coming of the Lord in his second coming, and to the end of our lives.
There is warning for us in this, but also consolation. The first reading sets before us the prophesy of Jeremiah for the salvation of Judah and Israel. Christians see this salvation shared with us also through Jesus Christ.
At the same time we do not presume that we live faultless lives – and so in the psalm we again ask the Lord to help us, and to lead us in the ways of righteousness.
The second reading encourages us to make the most of the opportunities we have to progress in the godly life, and may remind us of the continued prayer of the Church in heaven for the Church on earth.
The Gospel reading, too, encourages us to take care, to draw on the help the Lord offers to us, so that we may have confidence to come before the Lord when he comes. The Gospel acclamation makes this point very clearly: ‘Let us see, O Lord, your mercy and give us your saving help
The Lord will come, of course, not only at the end of time, but in our celebration of the Mass – in the gathered assembly, in the priest, in the word proclaimed and the Sacrament of the Sacrifice offered and shared in as Holy Communion.
The concluding prayer of the Mass encourages us to find in these mysteries present help to embrace the good God is and that God invites us to.
The Collect emphasises that we are not to be passive recipients of the grace of God, but urgent in our seeking for this help, and in our searching for the Lord himself.
The antiphon proposed for singing during the distribution of Holy Communion anticipates fruitfulness not only in us but in the world. As we leave Mass, grateful for what we have received, we might consider what we have received that we might share for the benefit, and salvation, of others too.
Photograph: (c) 2018, Allen Morris. Mosaic at Westminster Cathedral.