The Mass for this Sunday strikes me as a joyful one in the sense that the first reading from Isaiah says: "Remember not the events of the past, the things of long ago consider not; see, I am doing something new! Now it springs forth, do you not perceive it?"
Then the responsorial psalm has "The Lord has done great things for us; we are filled with joy." Psalm 126 tells us that the Lord has done great things for us and we are glad indeed.
Then the second reading is from Paul's Letter to the Phillipians where he says that he has accepted the loss of all things and considers them rubbish that "I may gain Christ and be found in him...I continue my pursuit toward the goal, the prize of God's upward calling, in Christ Jesus."
Then we come to the Gospel where Jesus is left alone with the woman who had committed adultery (where was the man?) and, after writing on the ground with his finger, finally said, "Let the one among you who is without sin be the first to throw a stone at her." When all had left, Jesus said to the woman, "Has no one condemned you?" then Jesus tells her that neither does he condemn her and she is to "go and from now on do not sin any more."
I guess this Mass is showing us that God is merciful and we have reason to rejoice. What is the new thing that God might be doing in our lives right now?