Those who refuse His mercy satisfy His justice in another way. Without His mercy, they cannot love Him. Without love for Him they cannot be 'justified' or 'made just'. That is to say: they cannot conform to Him Who is love. Those who have not received His mercy are in a state of injustice with regard to Him. It is their own injustice that is condemned by His justice. And in what does their injustice consist? In the refusal of His mercy. We come, in the end, to this basic paradox: that we owe it to God to receive from Him the mercy that is offered to us in Christ, and that to refuse this mercy is the summation of our 'injustice'. Clearly, then, only the mercy of God can make us just, in this supernatural sense, since the primary demand of God's justice upon us is that we receive His mercy.
~ Thomas Merton