Lamb of God for SATB choir and piano is a setting of the classic Agnus Dei prayer along with three other passages of scripture (Genesis 22.7–8, John 1.29–34, and Revelation 5.2–10, ESV translation) highlighting different aspects of the Second Person of the Holy Trinity, especially the sacrificial, sacramental, and eschatological. The Agnus Dei text functions as a foundation over which the other texts are sung, and the interaction between the classic liturgical text and the added passages draws out a different level of meaning than usually recognized. Several key elements serve to unify the piece, such as the general tonal centering on F-sharp, the motive of a unison expansion to a major second and then to a major third, and the use of the Lydian mode. These, in combination with a tone row of 13 pitches utilized frequently by the piano, help to create a unified harmonic palette of remarkable versatility, yielding both cold dissonances and sparkling sonorities.

Formally, the music follows the outline of the texts, but instead of creating three musically segregated sections, they are set as one organic whole having three clear parts. When the piece reaches the text ‘And they sang a new song’, for the first time (excluding the actual Agnus Dei text) the words are repeated, breaking away from the chant-like style. This builds until the music finally arrives gloriously on G-flat Lydian (enharmonically F-sharp) on the text of the heavenly hymn ‘Worthy are you’ as sung by the four living creatures and the twenty-four elders. However, as the hymn progresses, the Lydian inflection begins to cause the G-flat to feel unsettled and unfinished, and on the word ‘God’ on the penultimate line, the music finally arrives solidly on D-flat. It is there that it is revealed that the entire piece has been leading up to this plagal cadence, and that in this plagal cadence is the entire piece. The music ends with the choir quietly praying to the Lamb of God ‘grant us your peace’ as the piano echoes earlier material, primarily the tone row and the C-Lydian cluster chord which opened the piece, a chord formed by combining the six tones a semitone above and below the pitches of the D-flat major triad. This chord is played quietly three more times as the music gives way to silence.

Lamb of God was premièred on 20 November 2006 in Houghton, New York in the composer's senior composition recital All Things New, with the composer conducting and Robert Speicher, piano. (A recording of the performance is available here.) The chamber choir was comprised of: sopranos Rebekah Kenote, Ashlee Miller, Andrea O'Bryant, Susannah Smith, Alexis Swan, and Nicole Tascarella; altos Laura D'Amico, Rebecca Farley, Chelsea Keane, Elizabeth Thompson, and Alison Young; tenors Drew Burke, Ryan Ledabur, Daniel Liggett, Adam Potter, Brett Potts, James J. C. Schmieder, and Jeremiah Tyler; and basses Bradley Burr, David King, Nathan Majewski, Daniel Mullens, Christopher Olsen, and Jeff Walker. The composer is most in their debt.

Lamb of God, who takes away the sins of the world, have mercy on us.

And Isaac said to his father Abraham, “My father!” And he said, “Here am I, my son.” He said, “Behold, the fire and the wood, but where is the lamb for a burnt offering?” Abraham said, “God will provide for himself the lamb for a burnt offering, my son.” So they went both of them together.

Lamb of God, who takes away the sins of the world, have mercy on us.

The next day he saw Jesus coming toward him, and said, “Behold, the Lamb of God, who takes away the sin of the world!” And John bore witness: “I saw the Spirit descend from heaven like a dove, and it remained on him. I myself did not know him, but he who sent me to baptize with water said to me, ‘He on whom you see the Spirit descend and remain, this is he who baptizes with the Holy Spirit.’ And I have seen and have borne witness that this is the Son of God.”

Lamb of God, who takes away the sins of the world, grant us your peace.

And I saw a strong angel proclaiming with a loud voice, “Who is worthy to open the scroll and break its seals?” And no one in heaven or on earth or under the earth was able to open the scroll or to look into it. And one of the elders said to me, “Weep no more; behold, the Lion of the tribe of Judah, the Root of David, has conquered, so that he can open the scroll and its seven seals.”

And between the throne and the four living creatures and among the elders I saw a Lamb standing, as though it had been slain, with seven horns and with seven eyes, which are the seven spirits of God sent out into all the earth. And he went and took the scroll from the right hand of him who was seated on the throne. And when he had taken the scroll, the four living creatures and the twenty-four elders fell down before the Lamb, each holding a harp, and golden bowls full of incense, which are the prayers of the saints. And they sang a new song, saying,

“Worthy are you to take the scroll
  and to open its seals,
for you were slain, and by your blood you ransomed people for God
  from every tribe and language and people and nation,
and you have made them a kingdom and priests to our God,
  and they shall reign on the earth.”