The Pharisaical Jews could not understand how God would deal with His people by mercy and not judgment. They wanted to be dealt with by law, so the Mosaic Law was set down. God provided for them a completed set of rules and regulations that they could follow.

In time, they became totally wrapped up in the Law. As a result, they forgot the principle of God's mercy, even though God constantly reminded them of it. The tabernacle itself included a reminder: God dealt with them from above the mercy seat.
The prophet Micah addressed the religious leaders of his day, as well as the nation of Israel, when he said: He hath shewed thee, O man, what is good; and what doth the Lord require of thee, but to do justly, and to love mercy, and to walk humbly with thy God.
(Mic. 6:8)
These people had become so involved with their laws that they had forgotten justice, mercy and their walk with the Lord.

Jesus rebuked the religious leaders of His day for placing their traditions above the Word of God. He said that their traditions made the Word of God ineffective and that their worship was vain because they had left the Word for tradition (Mark 7:613).
In Matthew's Gospel, Jesus proclaimed:
But go ye and learn what that meaneth, I will have mercy, and not sacrifice: for I am not come to call the righteous, but sinners to repentance.
(Matt. 913)

But if ye had known what this meaneth, I will have mercy, and not sacrifice, ye would not have condemned the guiltless.
(Matt. 12:7)
In these scriptures, Jesus was referring to Hosea 6:6 which reads:
For I desired mercy, and not sacrifice; and the knowledge of God more than burnt offerings.
God's fervent desire is to deal with His people through mercy rather than judgment. Judgement will come if one does not avail himself of mercy, but God's mercy is "from everlasting to everlasting upon them that fear (reverence) Him" (Ps. 103:17).

Source: The Force Of Mercy by Buddy Harrison & Dr. Michael Landsman.
Excerpt permission granted by Harrison House Publishers