Even as the testimony of Christ was confirmed in you: As the testimony of Christ, etc. - The testimony of Christ is the Gospel which the apostle had preached, and which had been confirmed by various gifts of the Holy Spirit, and miracles wrought by the apostle.
Related Commentaries of 1 Corinthians 1:6
1 Corinthians 1:6
6 Even as the testimony of Christ was confirmed in you: