My tongue is both good and bad as it praises God at the same time it is negative toward others who have been made in God's likeness. It seems a sin of hypocrisy. How can my own tongue contradict itself? Yet it does. This should not be as it is impossible to have two attitudes or inner characters at the same time. This is the same as it being impossible for fresh water and salt water to flow from the same spring because the salt water would spread into the fresh water contaminating it. We were not created to have bad coming forth from our mouth any more than a fig tree was created to produce an olive or a grapevine to produce a fig. As a child of God, my tongue ought to be working out my genuine faith. However, this is an example of the very nature of the sin which is in me from birth. My faith continues to work from the inside outward as I live in this world. My mouth should be always glorifying God whether in direct praise of Him or by what it says to others. When I thank God for the good in a person my mind forgets the bad.
As in other verses in James, these verses compare with Sermon on the Mount in Matthew 7:15-20. False prophets are recognized by their sheep's clothing which bears bad fruit. "Are grapes gathered from thornbushes, or figs from thistles?"
Lord, purify my heart so that my words may be good, uplifting, peaceful, and always glorifying You.