Why is humility important according to Luke 18?

In the parable of the Pharisee and the publican (Luke 18:9-14), humility is emphasized as the path to being justified before God. The Pharisee's self-righteousness leads him to worship himself rather than God, while the publican, acknowledging his sin, humbles himself and pleads for mercy. The Lord teaches that 'everyone who exalts himself will be humbled' (Luke 18:14), emphasizing that it is through humbling ourselves and recognizing our need for grace that we are justified. This reflects a foundational aspect of Reformed theology, which teaches that salvation is by grace alone, not by works.