How do we know God's severity is a true concept?

The severity of God is a necessary aspect of His holiness and justice; it is affirmed by Scripture that God must punish all sin. Romans 2:6 emphasizes, 'Who will render to each one according to his deeds.' This highlights that God's judgment is based on truth and righteousness, aligning with His character. The consequences of rejecting Christ, as seen in the historical judgment of the Jewish nation for their unbelief, serve as a stern warning that God's severity is real and inevitable. Furthermore, the ultimate act of God's severity was demonstrated on the cross, where Christ bore the wrath intended for sinners, confirming the seriousness of divine justice against sin.