A person in Christ exhibits a longing for the new life and seeks to have the old things pass away, reflecting a genuine transformation of heart and mind.
To determine if someone is truly in Christ, one can observe the workings of their heart and the changes in their life. As Paul suggests in 2 Corinthians 5:17, the evidence of being in Christ is the passing away of old things and the realization of all things becoming new. This transformation manifests in a new understanding of God, oneself, and others, along with a desire to please God that was not present before. One might also examine their fruit, such as repentance from sin, an understanding of God's holiness and grace, and a desire to live in accordance with the teachings of Christ. This is not a passive state but involves active faith and continual turning toward Christ.
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