The reason it is my favorite is best seen in a detail:
In the readings for today's Mass, we hear: "With his every deed [King David] offered thanks to God Most High, in words of praise. With his whole being he loved his Maker and daily had his praises sung" (Sirach 47:8-9). I regret that the same cannot be said of me. Can it be said of you?
If we follow the angel's finger and focus on the Cross of our Lord instead of on our sufferings and sorrows, then we will, with David, give thanks to God in every deed and with every word, for in the Cross we see our salvation and lasting joy.