Psalms 103: 8 - 10, The LORD is merciful and gracious, slow to anger, and abounding in mercy. He will not always strive with us, nor will He keep His anger forever. He has not dealt with us according to our sins, nor punished us according to our iniquities. NKJV
The mercies of God are new every day. This is a good thing because humans are known to be repeat offenders. Isn't it great to know that we have a heavenly Father, who understands our weaknesses and faults? It's always encouraging and uplifting to read or hear about the goodness and mercy of God, but sometimes it can be hard to hear the requirements that God has for those who love Him. Doesn't Jesus require those of us who love Him to demonstrate our love by keeping His commandments? The gift of salvation is free, but once we become born again (redeemed from our sin debt), God has a purpose for our lives.
Our God is a merciful God; He loves sinners and broken people, but He is also a holy God, who hates sin. A God is merciful and kind toward us as sinners, He still requires us to repent of our sins and faults so that He can forgive us and cleanse us from all unrighteousness.
There's a story in Genesis about a man who killed his brother and asked God to have mercy "after" God had pronounced his sentence. God granted him mercy, but we don't see anywhere in the story where the man repented.
Genesis 4: 10 - 15, And He said, "What have you done? The voice of your brother's blood cries out to Me from the ground. So now you are cursed from the earth, which has opened its mouth to receive your brother's blood from your hand. When you till the ground, it shall no longer yield its strength to you. A fugitive and a vagabond you shall be on the earth." And Cain said to the LORD, "My punishment is greater than I can bear! Surely You have driven me out this day from the face of the ground; I shall be hidden from Your face; I shall be a fugitive and a vagabond on the earth, and it will happen that anyone who finds me will kill me." And the LORD said to him, "Therefore, whoever kills Cain, vengeance shall be taken on him sevenfold." And the LORD set a mark on Cain, lest anyone finding him should kill him. NKJV
While reading the above scripture, did you notice that Cain told God that his punishment was more than he could bear? Did you see the heart of God change toward Cain after he had pled his case? God granted him mercy because Cain asked for mercy. Why do you suppose God would grant an evil, murderous person mercy when he didn't repent of the sin that he had committed? Even though Cain had not repented of murdering his brother, he still had humbled himself (at least in this one area) by asking for God's mercy. God will not place more on us than we are able to bear. Therefore, Cain received the mercy he had asked God to give.
The accounts in the New Testament where Cain is mentioned show him as being evil. However, we must be careful not to jump too hastily and condemn Cain, lest we condemn ourselves. Didn't God look beyond our faults and send Jesus to die for our sins before we had an opportunity to repent? Even though God has granted us mercy instead of condemning all of mankind to eternal condemnation, we are still required to ask for forgiveness and to follow that request with a change of heart. (REPENTANCE)
Cain did receive mercy that day because God is merciful, but Cain didn't seek nor did he receive forgiveness for his sins. When God addressed Cain about his evil deeds, Cain did exactly what his father Adam did, he denied his sin. God won't always strive with us should we choose to ignore His forgiveness by not admitting our wrong doing and repenting of it before Him. If you have wronged someone and have committed a sin, but you haven't repented for it, then make things right. Today is the day of salvation through God's forgiveness and restoration. Confess what you have done before Him and ask Him to forgive you, and He will give you a clean heart. Not only will God grant you mercy, but He will also forgive you and He will wipe away every guilty stain with the precious blood of His Son through repentance.