How do we know we need a new heart?

The realization that we need a new heart stems from acknowledging our sinful condition. According to Jesus in Matthew 12:35, a good man produces good from a good heart, whereas an evil man brings forth evil from his evil heart. Since all have sinned (Romans 3:23), recognizing the need for transformation is crucial. We cannot love or serve God with our fleshly hearts, which ultimately leads to the stark necessity of a new heart from God that allows us to worship and obey Him authentically.