If we're looking for justice then we're looking for Jesus.
The message of the end of the book of Isaiah - which parallels the end of God's whole story of redemption - is that Jesus is coming again. He will come. He will right every wrong. He will fix everything broken. But bigger than just an aid to our troubles - even our greatest ones - He's coming. He - Jesus - Lord - King - is coming. Incomparable to our tragedy, trials, circumstances, pain, is Jesus. Isaiah 63-64 are a challenge and a reminder to us to not only expect the end, but to expect and look forward to Jesus.