The two

Romans 11:22
Behold then the kindness and severity of God; to those who fell, severity, but to you, God’s kindness, if you continue in His kindness; otherwise you also will be cut off.

The kindness and the severity of God. The two are blended together in a way not unlike the Incarnation itself.

The kindness of God—His gracious choice.  The severity of God—an admonition to those grafted in to continue in His kindness or otherwise to face judgement.

The two are blended together—God’s gracious choice and our faithful endurance, God’s kindness and His severity, the divine and human natures of Christ—inextricably, wonderfully.