Matthew Henry on 2 Corinthians 1:12-14

Though, as a sinner, the apostle could only rejoice and glory in Christ Jesus, yet, as a believer, he might rejoice and glory in being really what he professed. Conscience witnesses concerning the steady course and tenor of the life. Thereby we may judge ourselves, and not by this or by that single act. Our conversation will be well ordered, when we live and act under such a gracious principle in the heart. Having this, we may leave our characters in the Lord's hands, but using proper means to clear them, when the credit of the gospel, or our usefulness, calls for it.