if by that one verse, you are saying salvation is gained by obedience to the laws, you are indeed speaking of the cursed Gospel. you would have to throw out a lot of other scriptures.
Galatians 2:21
I do not frustrate the grace of God: for if righteousness come by the law, then Christ is dead in vain.
Faith is not that human illusion and dream that some people think it is. When they hear and talk a lot about faith and yet see that no moral improvement and no good works result from it, they fall into error and say, "Faith is not enough. You must do works if you want to be virtuous and get to heaven." The result is that, when they hear the Gospel, they stumble and make for themselves with their own powers a concept in their hearts which says, "I believe." This concept they hold to be true faith. But since it is a human fabrication and thought and not an experience of the heart, it accomplishes nothing, and there follows no improvement.
Faith is a work of God in us, which changes us and brings us to birth anew from God (cf. John 1). It kills the old Adam, makes us completely different people in heart, mind, senses, and all our powers, and brings the Holy Spirit with it. What a living, creative, active powerful thing is faith! It is impossible that faith ever stop doing good. Faith doesn't ask whether good works are to be done, but, before it is asked, it has done them. It is always active. Whoever doesn't do such works is without faith; he gropes and searches about him for faith and good works but doesn't know what faith or good works are. Even so, he chatters on with a great many words about faith and good works.
Faith is a living, unshakeable confidence in God's grace; it is so certain, that someone would die a thousand times for it. This kind of trust in and knowledge of God's grace makes a person joyful, confident, and happy with regard to God and all creatures. This is what the Holy Spirit does by faith. Through faith, a person will do good to everyone without coercion, willingly and happily; he will serve everyone, suffer everything for the love and praise of God, who has shown him such grace. It is as impossible to separate works from faith as burning and shining from fire. Therefore be on guard against your own false ideas and against the chatterers who think they are clever enough to make judgements about faith and good works but who are in reality the biggest fools. Ask God to work faith in you; otherwise you will remain eternally without faith, no matter what you try to do or fabricate.
Now justice is just such a faith. It is called God's justice or that justice which is valid in God's sight, because it is God who gives it and reckons it as justice for the sake of Christ our Mediator. It influences a person to give to everyone what he owes him. Through faith a person becomes sinless and eager for God's commands. Thus he gives God the honor due him and pays him what he owes him. He serves people willingly with the means available to him. In this way he pays everyone his due. Neither nature nor free will nor our own powers can bring about such a justice, for even as no one can give himself faith, so too he cannot remove unbelief. How can he then take away even the smallest sin? Therefore everything which takes place outside faith or in unbelief is lie, hypocrisy and sin (Romans 14), no matter how smoothly it may seem to go.
Or as in the 1689 Baptist Confession of Faith:
16.1 Good works are only those which God has commanded in his holy Word. [1] Works which do not have such warrant, and are invented by people out of blind zeal or on pretense of good intentions, are not good works. [2]
1. Micah 6:8 Romans 12:2 Hebrews 13:21 Colossians 2:3 2 Timothy 3:16-17 2. Matthew 15:9 with Isaiah 29:13 1 Peter 1:18 Romans 10:2 John 16:2 1 Samuel 15:21-23 1 Corinthians 7:23 Galatians 5:1 Colossians 2:8,16-23
16.2 These good works, done in obedience to God's commandments, are the fruits and evidence of a true and living faith. [1] By them believers express their thankfulness, [2] strengthen their assurance, [3] edify their brethren, [4] enhance their profession of the Gospel, [5] and silence the opponents [of the Gospel]. [6] So they glorify God whose workmanship they are, created in Christ Jesus to do good works [7] and to produce the fruits of holiness which lead to eternal life. [8]
1. James 2:18,22 Galatians 5:6 1 Timothy 1:5 2. Psalms 116:12-14 1 Peter 2:9,12 Luke 7:36-50 with Matthew 26:1-11 3. 1 John 2:3,5 1 John 3:18-19 2 Peter 1:5-11 4. 2 Corinthians 9:2 Matthew 5:16 5. Matthew 5:16 Titus 2:5,9-12 1 Timothy 6:1 1 Peter 2:12 6. 1 Peter 2:12,15 Titus 2:5 1 Timothy 6:1 7. Ephesians 2:10 Philippians 1:11 1 Timothy 6:1 1 Peter 2:12 Matthew 5:16 8. Romans 6:22 Matthew 7:13-14,21-23
16.3 Their ability to do these good works does not in any way come from themselves, but entirely from the Spirit of Christ. To enable them to do good works (besides the graces they have already received) they require the actual influence of the Holy Spirit to cause them to will and to do his good pleasure. [1] Yet are they not on this account to become negligent, nor to think that they are not required to perform a duty unless given a special impulse of the Spirit; rather, they ought to be diligent in stirring up the grace of God that is in them. [2]
1. Ezekiel 36:26-27 John 15:4-6 2 Corinthians 3:5 Philippians 2:12-13 Ephesians 2:10 2. Romans 8:14 John 3:8 Philippians 2:12-13 2 Peter 1:10 Hebrews 6:12 2 Timothy 1:6 Jude 1:20-21
16.4 Those who in their obedience [to God] attain the greatest height possible in this life, are still far from being able to perform works of supererogation (that is, to do more than God requires) since they fall short of much which, as their duty, they are required to do. [1]
1. 1 Kings 8:46 2 Chronicles 6:36 Psalms 130:3 Psalms 143:2 Proverbs 20:9 Ecclesiastes 7:20 Romans 3:9,23 Romans 7:14-15 Galatians 5:17 1 John 1:6-10 Luke 17:10
16.5 We cannot, even by our best works, merit pardon of sin or eternal life from the hand of God, for those works are out of all proportion to the glory to come. [1] Moreover, because of the infinite distance that is between us and God, our works can neither benefit God nor satisfy the debt of our former sins. When we have done all we can, we have only done our duty, and are still unprofitable servants. [2] Besides, if our works are good they originate from the Spirit, [3] and whatever we do is defiled and mixed with so much weakness and imperfection that it cannot endure the severity of God's judgment. [4]
1. Romans 8:18 2. Job 22:3 Job 35:7 Luke 17:10 Romans 4:3 Romans 11:3 3. Galatians 5:22-23 4. 1 Kings 8:46 2 Chronicles 6:36 Psalms 130:3 Psalms 143:2 Proverbs 20:9 Ecclesiastes 7:20 Romans 3:9,23 Romans 7:14-15 Galatians 5:17 1 John 1:6-10
16.6 Yet, although believers are accepted as individual people through Christ, their good works also are accepted in Christ. [1] It is not as though in this life they were entirely blameless and beyond censure in God's sight, [2] but that he looks upon them in his Son, and is pleased to accept and reward what is sincere, even though it is accompanied by many weaknesses and imperfections. [3]
1. Exodus 28:38 Ephesians 1:6-7 1 Peter 2:5 2. 1 Kings 8:46 2 Chronicles 6:36 Psalms 130:3 Psalms 143:2 Proverbs 20:9 Ecclesiastes 7:20 Romans 3:9,23 Romans 7:14-15 Galatians 5:17 1 John 1:6-10 3. Hebrews 6:10 Matthew 25:21,23
16.7 As for works done by the unregenerate, even though in essence they may be things which God commands, and may be beneficial both to themselves and others, [1] yet they remain sinful works because they do not proceed from a heart purified by faith, [2] nor are they done in a right manner according to the Word, [3] nor is their purpose the glory of God. [4] Therefore such works cannot please God nor make a person acceptable to receive grace from God. [5] Yet the neglect of such works is even more sinful and displeasing to God. [6]
1. 1 Kings 21:27-29 2 Kings 10:30-31 Romans 2:14 Philippians 1:15-18 2. Genesis 4:5 with Hebrews 11:4-6 1 Timothy 1:5 Romans 14:23 Galatians 5:6 3. 1 Corinthians 13:3 Isaiah 1:12 4. Matthew 6:2,5-6 1 Corinthians 10:31 5. Romans 9:16 Titus 1:15 Titus 3:5 6. 1 Kings 21:27-29 2 Kings 10:30-31 Psalms 14:4 Psalms 36:3