So you're sitting in judgment on how God chose to inspire Scripture, eh?
That's a lot of chutzpah.
Paul expressed no such excess. His teachings were these, which destroys your assumption that salvation by faith alone leads to wanton, excess sinning.
Romans 6:1-4 What shall we say then? Are we to continue in sin that grace may abound? By no means! How can we who died to sin still live in it? Do you not know that all of us who have been baptized into Christ Jesus were baptized into his death? We were buried therefore with him by baptism into death, in order that, just as Christ was raised from the dead by the glory of the Father, we too might walk in newness of life.
Romans 6:12-18 Let not sin therefore reign in your mortal body, to make you obey its passions. Do not present your members to sin as instruments for unrighteousness, but present yourselves to God as those who have been brought from death to life, and your members to God as instruments for righteousness. For sin will have no dominion over you, since you are not under law but under grace.
What then? Are we to sin because we are not under law but under grace? By no means! Do you not know that if you present yourselves to anyone as obedient slaves, you are slaves of the one whom you obey, either of sin, which leads to death, or of obedience, which leads to righteousness? But thanks be to God, that you who were once slaves of sin have become obedient from the heart to the standard of teaching to which you were committed, and, having been set free from sin, have become slaves of righteousness.
Philippians 1:9-11 And it is my prayer that your love may abound more and more, with knowledge and all discernment, so that you may approve what is excellent, and so be pure and blameless for the day of Christ, filled with the fruit of righteousness that comes through Jesus Christ, to the glory and praise of God.
Ephesians 2:8-10 For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast.
For we are his workmanship, created in Christ Jesus for good works, which God prepared beforehand, that we should walk in them.
Nowhere ever did Paul ever suggest, imply, or condone the thinking that now that we are saved by grace through faith that it's a license to sin.
That's purely a fabricated accusation leveled against Christians in a vain attempt to impose works based religion on people.
It's also pretty telling about what the person would do if THEY honestly, really believed that salvation was by faith.
Nowhere ever did Paul ever suggest, imply, or condone the thinking that now that we are saved by grace through faith that it’s a license to sin.
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Paul may want to argue that salvation purely through grace is no licence to sin, but it’s like communism. It sounds good in theory, but when you put it into practice, it’s defects become obvious.