Definition and Overview:
True righteousness, as depicted in the Bible, is an internal state of being that aligns with God's standards and is reflected in one's thoughts, intentions, and actions. It transcends mere external adherence to laws and rituals, emphasizing the transformation of the heart and mind. This concept is central to the teachings of both the Old and New Testaments, where the focus is on a genuine relationship with God rather than superficial compliance.

Old Testament Insights:
The Old Testament lays the groundwork for understanding true righteousness as an internal quality. In 1 Samuel 16:7, the Lord instructs Samuel, "Do not consider his appearance or his height, for I have rejected him. The LORD does not see as man does. For man sees the outward appearance, but the LORD sees the heart." This verse highlights that God values the condition of the heart over external appearances.

The Psalms and Proverbs frequently emphasize the importance of a pure heart. Psalm 51:10 pleads, "Create in me a clean heart, O God, and renew a right spirit within me." Similarly, Proverbs 4:23 advises, "Guard your heart with all diligence, for from it flow springs of life." These passages underscore the belief that true righteousness originates from within and influences one's entire being.

New Testament Teachings:
The New Testament further develops the theme of internal righteousness, particularly through the teachings of Jesus Christ. In the Sermon on the Mount, Jesus contrasts the external righteousness of the Pharisees with the internal righteousness required by God. Matthew 5:20 states, "For I tell you that unless your righteousness exceeds that of the scribes and Pharisees, you will never enter the kingdom of heaven."

Jesus emphasizes the internal nature of righteousness in Matthew 5:21-22 and 5:27-28, where He expands the understanding of commandments against murder and adultery to include anger and lustful thoughts, respectively. These teachings illustrate that true righteousness involves the transformation of one's inner life, not just outward compliance.

The Apostle Paul also addresses the internal aspect of righteousness in his epistles. In Romans 2:28-29 , he writes, "A man is not a Jew because he is one outwardly, nor is circumcision only outward and physical. No, a man is a Jew because he is one inwardly, and circumcision is a matter of the heart, by the Spirit, not by the written code." Paul emphasizes that true righteousness is a matter of the heart, brought about by the Holy Spirit.

Role of the Holy Spirit:
The Holy Spirit plays a crucial role in cultivating true righteousness within believers. According to Galatians 5:22-23 , "But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness, and self-control. Against such things there is no law." These virtues are evidence of the Spirit's work in transforming the believer's heart and mind, leading to genuine righteousness.

Practical Implications:
True righteousness being internal has significant implications for Christian living. It calls believers to examine their motives and desires, seeking to align them with God's will. This internal focus encourages a life of integrity, where actions are consistent with one's faith and values. It also fosters humility, as believers recognize their dependence on God's grace and the Holy Spirit for true transformation.

Conclusion:
The biblical concept of true righteousness as internal challenges believers to pursue a deep, authentic relationship with God, marked by a transformed heart and mind. This internal righteousness is not self-generated but is a work of the Holy Spirit, resulting in a life that reflects God's character and love.