Jesus opens His Heart to us in the Beatitudes and declares “blessed are they who hunger and thirst for righteousness” (Mt. 5:6). We are to crave righteousness with our very being. But what is righteousness? Pope Benedict observes that “righteousness in the language of the Old Covenant is the term for fidelity to the Torah.” For the observant Jews of Jesus’ time (including Jesus Himself), righteousness is openness and obedience to God’s word.
What this means is that we cannot define for ourselves what it is to be righteous—there is a specific content and concrete demands. If I myself set the standard for my own righteousness, and then declare to all that I have met my standards, I am not righteous, but self-righteous. This is the error of the Pharisees. If you seek to be righteous, strive to do so not by your own standards, but God’s.