In saying that He desires mercy and not sacrifice, Jesus is teaching that He prefers it when people practice mercy and not blindly follow ritual. He is not condemning the laws of sacrifice that He set up for Israel to practice until He fulfilled them, but explaining that He is more pleased with acts of forgiveness and kindness than strict external compliance to the law.
He is telling the Pharisees that, though they were exacting in keeping the letter of the law, they had completely missed its intent. In Matthew 23:23, He reminds them of this very point: "Woe to you, scribes and Pharisees, hypocrites! For you pay tithe of mint and anise and cummin, and have neglected the weightier matters of the law: justice and mercy and faith. These you ought to have done, without leaving the others undone."
It is good and right to tithe to God, even to be exacting in our accounting, but not at the expense of the far more important matters of justice, mercy, and faith! These weightier matters are a Christian's priorities, so if a question of "What do I do?" ever comes up between practicing them and keeping the strict letter of the law, our judgment should lean toward these Christian virtues. If we can do both, all the better!
Jesus Christ is the personification of mercy. Exodus 25:17-22 describes the Mercy Seat constructed in the wilderness. Essentially, it was the golden lid of the Ark of the Covenant, on which were figures of two cherubim facing each other with their wings stretched out, covering the Mercy Seat. God, the pre-incarnate Christ, says in verse 22, "And there I will meet with you, and I will speak with you from above the mercy seat, from between the two cherubim which are on the ark of the Testimony." The Mercy Seat represented God in His dealings with sinful humanity, and the chief element He employs is mercy.
Now notice Romans 3:23-25:
. . . for all have sinned and fall short of the glory of God, being justified freely by His grace through the redemption that is in Christ Jesus, whom God set forth as a propitiation by His blood, through faith, to demonstrate His righteousness, because in His forbearance God had passed over the sins that were previously committed. . . .
This passage tells us that Jesus Christ is our Mercy Seat, but the translators have hidden it. "Propitiation" (Greek hilasterios) in verse 25 is literally "place of conciliation or expiation" or "Mercy Seat." The Septuagint used hilasterios to translate the Hebrew noun kapporeth ("Mercy Seat"). This Hebrew word's root is kapar meaning "to cover" or "to conceal." This illustrates that the nature of God is to be merciful.
The apostle Peter writes in I Peter 2:21 that we are to follow in Christ's steps, thus as Jesus Christ is merciful, we also are to show mercy in our judgments.
John O. Reid (1930-2016)
Mercy: The Better Option