I. We Have Sinned, and Greatly Need God's Mercy (Psalm 51)
The Responsorial Psalm is Psalm 51, which David sang/prayed after confessing his affair with Bathsheba. The Psalm goes:
Have mercy on me, God, in Your goodness; in Your abundant compassion blot out my offense.Wash away all my guilt; from my sin cleanse me.For I know my offense; my sin is always before me.Against You alone have I sinned; I have done such evil in Your sight
That You are just in Your sentence, blameless when You condemn.True, I was born guilty, a sinner, even as my mother conceived me.Still, You insist on sincerity of heart; in my inmost being teach me wisdom.Cleanse me with hyssop, that I may be pure; wash me, make me whiter than snow.Let me hear sounds of joy and gladness; let the bones You have crushed rejoice.Turn away Your face From my sins; blot out all my guilt.A clean heart create for me, God; renew in me a steadfast spirit.Do not drive me from Your presence, nor take from me Your Holy Spirit.Restore my joy in Your salvation; sustain in me a willing spirit.I will teach the wicked Your ways, that sinners may return to You.Rescue me from death, God, my saving God, that my tongue may praise Your healing power.Lord, open my lips; my mouth will proclaim your praise.For You do not desire sacrifice; a burnt offering You would not accept.My sacrifice, God, is a broken spirit; God, do not spurn a broken, humbled heart.Make Zion prosper in Your good pleasure; rebuild the walls of Jerusalem.Then You will be pleased with proper sacrifice, burnt offerings and holocausts; then bullocks will be offered on your altar.
This has to be one of my favorite Psalms. It's also theologically rich. From it, we know that original sin exists (Psalm 51:7), but that this is no excuse for the sins that we commit (Ps. 51:8), that the Lord will forgive anyone who turns to Him (Ps. 51:15), and that in the forgiveness of God, our scarlet sins are washed away, and we're made whiter than snow. This concept supports the notion of regenerative Baptism - that in the "one Baptism for forgiveness of sins," we're washed clean of our sins, and a clean heart and a steadfast spirit is created within us. It also points to the Passover and to Christ with the reference to "hyssop." Hyssop is what the lamb's blood is soaked in for the Passover (Exodus 12:22), and what the wine vinegar was on when it was pressed to Jesus' lips on the Cross (John 19:29). In both cases, it's tied to being washed clean through the Blood of the Lamb. Finally, "let the bones You have crushed rejoice" is such a beautiful sentiment. David wants the shame, humiliation, and remorse that he's feeling to be a channel for good, so that one day, he'll look back and be thankful, even thrilled, that God punished him. That's what mature ownership of your sins looks like.
II. Through Fasting and Genuine Repentance, God Will Have Mercy (Joel 2)
The First Reading comes from Joel 2:12-18. To provide some background, Joel is warning the sinful people of Israel that because of their sins, God is going to lift His Hand of protection and let Israel's enemies sweep in and crush them. Joel concludes this warning, "For great is the day of the LORD, and exceedingly terrible; who can bear it?" But then he shifts tone completely, reminding the people of God's everlasting Mercy:
Once the people realize the gravity of their sins, once they're face to face with what they truly deserve, they repent, and God has mercy upon them. More than this, He blesses them, and promises to pour out His Holy Spirit on them (Joel 2:28-32). It's unmerited grace upon unmerited grace upon unmerited grace.Yet even now, says the LORD, return to me with your whole heart, with fasting, and weeping, and mourning;
Rend your hearts, not your garments, and return to the LORD, your God. For gracious and merciful is he, slow to anger, rich in kindness, and relenting in punishment.Perhaps he will again relent and leave behind him a blessing, Offerings and libations for the LORD, your God.Blow the trumpet in Zion! proclaim a fast, call an assembly;Gather the people, notify the congregation; Assemble the elders, gather the children and the infants at the breast; Let the bridegroom quit his room, and the bride her chamber.Between the porch and the altar let the priests, the ministers of the LORD, weep, And say, "Spare, O LORD, your people, and make not your heritage a reproach, with the nations ruling over them! Why should they say among the peoples, 'Where is their God?'"Then the LORD was stirred to concern for his land and took pity on his people.
III. This Forgiveness is Through the Blood of Christ (2 Corinthians 5-6)
The Second Reading is straight to the point, from 2 Corinthians 5:20-6:2
So we are ambassadors for Christ, as if God were appealing through us. We implore you on behalf of Christ, be reconciled to God.The third sentence, beginning "For our sake," is a great encapsulation of the Atonement. Christ is the One whose sinless Offering, as both Victim and High Priest, atones for our sins to God and makes us right with Him.
For our sake He made Him to be sin who did not know sin, so that we might become the righteousness of God in Him.
Working together, then, we appeal to you not to receive the grace of God in vain.
For He says: "In an acceptable time I heard you, and on the day of salvation I helped you." Behold, now is a very acceptable time; behold, now is the day of salvation.
IV. God Desires that We Rend Our Hearts, Not Boast in Our Fasting (Matthew 6)
The Gospel is taken from two chunks of Matthew 6 - v. 1-6, and v. 16-18 (in between these two passages is the Our Father, which we pray later in the Mass). Up to this point, we've seen in both Psalm 51 and Joel 2 that what God is looking for is contrition, not sacrifices. The sacrifices are only good if we first are truly sorry for our sins (that's Psalm 51:19-21), and the point of the fast in Joel 2 is internal, not external. Jesus makes the same point saying:
"(But) take care not to perform righteous deeds in order that people may see them; otherwise, you will have no recompense from your heavenly Father.
When you give alms, do not blow a trumpet before you, as the hypocrites do in the synagogues and in the streets to win the praise of others. Amen, I say to you, they have received their reward.But when you give alms, do not let your left hand know what your right is doing,so that your almsgiving may be secret. And your Father who sees in secret will repay you."When you pray, do not be like the hypocrites, who love to stand and pray in the synagogues and on street corners so that others may see them. Amen, I say to you, they have received their reward.But when you pray, go to your inner room, close the door, and pray to your Father in secret. And your Father who sees in secret will repay you.
But when you fast, anoint your head and wash your face, so that you may not appear to be fasting, except to your Father who is hidden. And your Father who sees what is hidden will repay you.It's a fascinating passage, because while condemning the works performed by the Pharisees, Jesus simultaneously promises a reward to those who perform these good works secretly, rather than out of a desire for the praises of men. His point, obviously, isn't that every good work has to be secret, but that all good works should be motivated by the right goal: to please, honor, and serve God, rather than making ourselves look like a great person.
The single biggest spiritual danger a person can face in fasting is thinking of themselves as a great person for fasting. If you were a great person, you wouldn't need to be fasting. Here we come full circle to Psalm 51 and Joel 2. David is reminded of his sins by Nathan (Ps. 51:2); the Israelites are reminded of theirs by Joel. Only at this point do they turn away from sin and back towards God. The Pharisees, in turning fasting into a point of pride, have forgotten the very knowledge that can save them - that they, like David, the Israelites, you and me - are sinners in terrible need of God's Mercy.