What is Mercy?
Mercy comes from God and He and His Son are one (John 10:30) since God is Love (1 John 4:8) and Mercy comes from Love so too Justice comes from Love... So Mercy and Justice are not divorced from one another as Love rejoices in truth (1 Cor 13:6) and what is truth? Truth is Jesus (1 John 14:6) and Truth is the very principle of Justice, so it is fair to say that Justice is also Jesus.
"Your throne, O god, stands forever; your royal scepter is a scepter for justice. You love justice and hate wrongdoing; therefore God, your God, has anointed you with the oil of gladness above your fellow kings." Psalm 45:7-8
Talking about Mercy alone is an illusion, an idea that could only be sold by the devil himself, like Mercy understands sin, that it celebrates the sinful nature of men, because God is Love and His Mercy has no bounds (which is true), like if Mercy would stop Justice forever (which is not true) once Mercy comes in Justice will also do God's will, if you repent with a true a sincere heart Mercy will be given and the grace to walk towards holiness, pain will be the result of that Justice which will sanctify us all, pain to those who have repented with contrite hearts (Hebrews 12:6-11) so this means, the repentant thief will return what was stolen and depending on the situation, a little suffering will satisfy his conversion by paying to society his bad deeds... Many examples to portray... but a little suffering coming from a little chasticement to teach righteousness, will suffice, as the Master and Teacher is Just and Merciful as He is Love.
"Divine Love from the affected (God) to the aggressor (us)" that's Divine Mercy and immediately after Justice: righteousness, taight in discipline if you are willing to follow the Lord, if your not, then Justice will call out for vengeance for those affected by your iniquity... This is why the most sincere call from both Mercy and Justice is:
"The Kingdom of God is at hand REPENT and BELIEVE in the Gospel." Mark 1:15
If you truly repent Mercy will be yours, if you believe, Justice will be yours, if you follow the Lord's discipline, suffering will come as your call is to be perfect as your Almighty Father is perfect (Mat 5:48) proclaiming Mercy without Justice is a mirage, an illusion... every time Jesus spoke of Mercy, afterwards He spoke of Justice the most brightest example was the Sermon of the mount as Jesus talked about how Mercy acted and How Justice acted... Jesus said 9 times blessed those who are for God and how those who are not for God, He compared them as salt without flavor:
“You are the salt of the earth. But if the salt loses its saltiness, how can it be made salty again? It is no longer good for anything, except to be thrown out and trampled underfoot. Mat 5:17
Therefore to walk towards holiness the first thing is a contrite heart asking for forgiveness, then Divine Mercy will find you, but, if you truly are contrite, you will embrace Justice and accept pain, discipline will find you, then Love and Fear for the Lord will grow... you will embrace His commandments and strive for perfection.
May you see the Lord in everything, may you rejoice in suffering out of Love for whom suffered first, may you embrace Mercy with Justice and act according to it. Amen