For sin will have no dominion over you, since you are not under law but under grace.
(Romans 6:14 ESV)
Romans 6:14 best explains the principle behind this controversial phrase. This verse reflects that a Christian who is truly pardoned by grace, would always have the will to be sanctified from his sins. A heart that knows his wretchedness and is humbled by the loving kindness of the Lord, would always seek forgiveness to the One who is perfect, for he understands that in his fallen state, he could still sin both knowingly and unknowingly. Yet since Jesus captured his heart, sin would no longer master him, he has a sure hope that leads him to the redemption of Christ through grace.
And as we relent on our everyday shortcomings to the Lord, we are reminded in the Holy Scripture to "bear fruit in keeping with repentance". Thus, we cannot misinterpret that while our calling is irrefutable ~ "My Father, who has given them to me, is greater than all, and no one is able to snatch them out of the Father's hand." (John 10:29 ESV), we can do whatever pleases us, without consideration to our holy calling.
Matthew 7:16 ESV says "You will recognize them by their fruits. Are grapes gathered from thornbushes, or figs from thistles?" The doctrine of our faith must lead us to be Christ-like, with all we are, we are sanctified, from glory to glory.
Matthew Henry's Commentary explains
Let's examine our doctrine and its effects on us. The Christian doctrine is not about sinning as you like and asking for forgiveness whenever it pleases you. I would like again to quote from Gil Exposition of the Entire Bible:
The evidence that we possess the true salvation of God is not merely based on our profession and claim that we are followers of Christ, but through the level of our obedience to Him.
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