The readings for the last Sunday of the Church Year are from Isaiah 51:4–6; Jude 20-25; and Mark 13:24–37.
The church calendar was designed, from ancient times, to help do exactly what today’s lessons are urging: be watchful!
Isaiah 51 includes lots of language about the end of the world. Some words sound threatening, and some comforting, and all of it depends on the last verses that describe the nature of God: steady, stable, reliable, strong, and most of all, focused on saving us (read on to Isaiah 53 for a whole chapter on how the Son of God saved us).
Jude works the same way as Isaiah. Jude has commands for us to be watchful and careful. But those commands rest on God, who is not only able to do everything that our life depends on, but who loves to do everything for our lives. The law always turns our attention to God’s grace: for forgiveness because we need it and for His Spirit who is at work in us to succeed.
Mark records Jesus talking about the end of the world. Mark 13 begins with the apostles’ distraction with buildings of human construction. Contrast that with the body of Jesus: The Stone that the builders rejected; the tabernacle that the one in the OT was pointing forward to; God with us, in the midst of us. In the middle of Mark’s lesson is what matters: My Word will never pass away, or change, or be broken. How do we know if we are among the elect whom the angels of God will gather? We have objective means provided by God in our baptism, our steady reception of His Holy Supper, our accessing His absolution, and our life in His Word!