Today I am vested in blood-red vestments because at the beginning of Holy Week we are anticipating the week’s end.  The One who enters Jerusalem today is already, in the words of the poet Keats, a “murdered man.” It is blood that we should be thinking about.  You might say, so what? There is so much bloodshed in the world: in car accidents, in murders, in natural disasters, in war. Yes, but this blood is different.

    This is redemptive blood.  It is the blood that St. Catherine of Siena saw as soaking the Church in its flow.  It is royal blood, the blood of the Messiah, to be shed in a self-giving whose effects are so wonderful that the Sacrifice is a triumph, and not a defeat.  The red that cloths us today is also the red of regal triumph.

    Today our Lord sought to enter his own city, Jerusalem, the holy city, whose calling was to be the dwelling-place on earth of the truth, beauty, and goodness of God.  Jerusalem belongs to Jesus because in his person -- fully human and fully divine -- Jesus is the measure of truth, beauty and goodness.

    Despite the hosannas of today’s entrance, by the end of this week Jerusalem will close its doors on Jesus.  It will have him crucified outside its gates.

    How often have we known this in our own lives?  We close the door of our hearts, when to have opened them would mean healing ourselves and others.  On Good Friday Jesus will do the opposite. He will open his arms as wide as they can go, so that all the world may march in through his pierced side, into the spacious welcome of his Sacred Heart.

[This homily is largely taken from Fr. Aidan Nichols, OP, Year of the Lord's Favour: A Homiliary for the Roman Liturgy. Volume 2: The Temporal Cycle Advent and Christmastide, Lent and Eastertide]