Father Jason examines Psalm 80, which is appointed for Advent IV, Year A in the RCL. Psalm 80 is a reflection on repentance, and having the mature faith to call upon God for God to turn God's countenance toward us.
Links to research sources:
Rev. Jason Byassee's reflection on Working Preacher
James Mays book on the Psalms for the Interrpretation series.