This is Paul Mason’s setting for Psalm 72 for the Second Sunday in Advent Year A, as found in his book Psalms For All Time Vol 2.
The psalm is also used in hope in a mass in time of war.
The refrain is, “Justice shall flourish in his time, and fullness of peace forever.” The verses are Psalm 72: 2, 7-8, 12-13, 17.