Could I get into this conversation, too? I hope you do mind?
I will post the most frequent verses that support OSAS, in a separate Post after this post.
But your question of the two portions of Scripture should be answered first, AND we must realize that Mat. 7:13-27, has a lot to do with it.
In Gal. 5:19-21 you absolutely have to read the THE WHOLE CONTEXT, to precisely understand what HE IS SAYING.
Galatians 5:11-26 (HCSB)
11 Now brothers, if I still preach circumcision, why am I still persecuted? In that case the offense of the cross has been abolished.
12 I wish those who are disturbing you might also get themselves castrated!
13 For you were called to be free, brothers; only don’t use this freedom as an opportunity for the flesh, but serve one another through love.
14 For the entire law is fulfilled in one statement: Love your neighbor as yourself.
15 But if you bite and devour one another, watch out, or you will be consumed by one another.
16 I say then, walk by the Spirit and you will not carry out the desire of the flesh.
17 For the flesh desires what is against the Spirit, and the Spirit desires what is against the flesh; these are opposed to each other, so that you don’t do what you want.
18 But if you are led by the Spirit, you are not under the law.
19 Now the works of the flesh are obvious: sexual immorality, moral impurity, promiscuity,
20 idolatry, sorcery, hatreds, strife, jealousy, outbursts of anger, selfish ambitions, dissensions, factions,
21 envy, drunkenness, carousing, and anything similar. I tell you about these things in advance—as I told you before—that those who practice such things will not inherit the kingdom of God.
22 But the fruit of the Spirit is [Agape, Rom. 5:5] love, joy, peace, patience, kindness, goodness, faith,
23 gentleness, self-control. Against such things there is no law.
24 Now those who belong to Christ Jesus have crucified the flesh with its passions and desires.
25 Since we live by the Spirit, we must also follow the Spirit.
26 We must not become conceited, provoking one another, envying one another.
Now it is much easier to understand what Paul is saying. He is confronting Judaisers, who were falsely saying men had to Circumcised before they can become a Christian. All he was saying is exactly what JESUS taught in Mat. Chapter 7. That when you truly have COME to KNOW HIM intimately, receiving HIM as LORD, meaning MASTER; that BORN AGAIN EXPERIENCE will change you, because YOU will have a NEW NATURE in your Human Spirit. The verses you quoted are the typical old Nature of someone who has NOT been Born Again. The NATURE, is the DOMINANT LIFESTYLE CHARACTERISTICS, of the person in question. YES, we SIN, but as a Christian Matures, we will sin LESS, and LESS, and LESS. It is not the DOMINANT LIFESTYLE CHARACTERISTICS to continue to SIN like the Old Human Nature.
Matthew 7:23 (HCSB)
23 Then I will announce to them, ‘I never knew you! Depart from Me, you lawbreakers!’
That is referring to the Born Again experience, when the Holy Spirit birthed our Human Spirit, and gave it a NEW NATURE, which is described in Gal. 5:22-26.
Matthew 7:20 (HCSB)
20 So you’ll recognize them by their fruit.
Christ said we can recognize whether or not a person has been Born Again, just by examining their FRUIT. FIRST you have to realize a baby Christian does not produce much fruit. So you have to watch someone for maybe a year or more to find out if the FRUIT OF THE SPIRIT, is starting to manifest itself. If you see NOTHING but bad fruit such as an unhealthy interest in:
hatreds, strife, jealousy, outbursts of anger, selfish ambitions, dissensions, factions, envy, etc.; then you can be certain that they have never been born again, YET. If you can detect Self Sacrificial love, joy, peace, patience, kindness, goodness, faith, gentleness, self-control, as their New Nature, even if in your opinion they have some things wrong, you should respect him as a Christian Brother.
Your other question on 1 Corinthians 6:9-11:
There are a number of SINS listed in these verses, but remember they are not one time sins, but they are UNREPENTANT, or LIFESTYLE OF SINNING. A great deal of confusion between the GREEK TEXT and the ENGLISH TEXT lies in the FACT, that the Greeks have six Primary Verb Tenses, where as in English, we only have three Primary Verb Tenses. Such a verb is:
1 John 2:4 (HCSB)
4 The one who says, “I have come to know Him,” yet doesn't keep His commands, is a liar, and the truth is not in him.
That Greek Verb "Keep", does not imply PERFECTION, but an ongoing lifestyle of striving to KEEP. So English is a POOR Language at Best, to translate the Bible into. No I am not a Greek Scholar, but I know the TOOLS and How to look the TENSES up in them.
1 Corinthians 6:9-11 (HCSB)
9 Don’t you know that the unrighteous will not inherit God’s kingdom? Do not be deceived: No sexually immoral people, idolaters, adulterers, or anyone practicing homosexuality,
10 no thieves, greedy people, drunkards, verbally abusive people, or swindlers will inherit God’s kingdom.
11 And some of you used to be like this. But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ and by the Spirit of our God.
Therefore the first clue to how to properly interpret these scriptures, is the WORD unrighteous. Paul knows and preached that we inherit the RIGHTEOUSNESS of Christ, when we are Born Again. Therefore he is talking about Unrepentant Sinners that have NEVER BEEN SAVED. AND some of us USED TO LIKE THAT. But we were Born Again, and now our NEW NATURE in our HUMAN SPIRIT, is Characterized by the FRUIT of the SPIRIT: Agape love, joy, peace, patience, kindness, goodness, faith, gentleness, self-control, and the like. Remember A Born Again Christian is one who sins LESS, and Less, and LESS.
And you may want to say, "But what about verses that seem to imply a Christian does not SIN."
1 Thessalonians 4:7 (HCSB)
7 For God has not called us to impurity but to sanctification.
Sanctification is a lifelong process where we will strive to get the SIN out of our lives, and we will not be perfect until the we get the Glorified Body, in the Resurrection. Interestingly, the New Century Version, words that verse this way:
1 Thessalonians 4:7 (NCV)
7 God called us to be holy and does not want us to live in sin.
Romans 6:12 (ESV)
12 Let not sin therefore reign in your mortal body, to make you obey its passions.
Again it does not mean we can be SINLESS, but it does mean we do not let it Reign or Dominate us.
1 John 3:9 (HCSB)
9 Everyone who has been born of God does not sin, because His seed remains in him; he is not able to sin, because he has been born of God.
Again that does not imply PERFECTION, but a Lifestyle of Striving to do no sin, even though we are not PERFECT. You will find that John is VERY FOND of the Greek Perfect Tense (not the English meaning of that word perfection), but HE USES IT A LOT, and also the AORIST TENSE, which carries a similar Meaning. Neither of which we have in ENGLISH.
I will post the PRIMARY Verses that SUPPORT OSAS FAITH, in my next Post.