@Chris_Sims That is a great question. Even in the New Testament Church people had a tendency to abuse God’s grace or to stray into legalism. So we see in Ephesians Paul emphasizing that we are saved purely by grace.
Ephesians 2:8-10 - For it is by grace you have been saved, through faith—and this is not from yourselves, it is the gift of God— 9 not by works, so that no one can boast. 10 For we are God’s handiwork, created in Christ Jesus to do good works, which God prepared in advance for us to do.
Then in Romans we see Paul having to rebuke those trying to take advantage of God’s grace. If we have died with Christ - how can we continue on in sin? God forbid!
Romans 6:1-2 - What shall we say, then? Shall we go on sinning so that grace may increase? 2 By no means! We are those who have died to sin; how can we live in it any longer?
In Galatians 5 (or Romans 6-8) we see a brilliant exposition of this reality - we are not under the law but under the Spirit. And those who are filled with God’s Spirit do not gratify the desires of the flesh and do not envy / provoke one another. To walk in the Spirit is to walk in love - to produce the fruit of the Spirit in our lives.
Galatians 5:13-25 - You, my brothers and sisters, were called to be free. But do not use your freedom to indulge the flesh; rather, serve one another humbly in love. 14 For the entire law is fulfilled in keeping this one command: “Love your neighbor as yourself.” 15 If you bite and devour each other, watch out or you will be destroyed by each other.
16 So I say, walk by the Spirit, and you will not gratify the desires of the flesh. 17 For the flesh desires what is contrary to the Spirit, and the Spirit what is contrary to the flesh. They are in conflict with each other, so that you are not to do whatever you want. 18 But if you are led by the Spirit, you are not under the law.
19 The acts of the flesh are obvious: sexual immorality, impurity and debauchery; 20 idolatry and witchcraft; hatred, discord, jealousy, fits of rage, selfish ambition, dissensions, factions 21 and envy; drunkenness, orgies, and the like. I warn you, as I did before, that those who live like this will not inherit the kingdom of God.
22 But the fruit of the Spirit is love, joy, peace, forbearance, kindness, goodness, faithfulness, 23 gentleness and self-control. Against such things there is no law. 24 Those who belong to Christ Jesus have crucified the flesh with its passions and desires. 25 Since we live by the Spirit, let us keep in step with the Spirit. 26 Let us not become conceited, provoking and envying each other.
True religion in the Bible always involves being set apart from the world and keeping God’s commandments. Love involves obedience.
James 1:27 - Religion that God our Father accepts as pure and faultless is this: to look after orphans and widows in their distress and to keep oneself from being polluted by the world.
John 14:21 - Whoever has my commands and keeps them is the one who loves me. The one who loves me will be loved by my Father, and I too will love them and show myself to them.
I John 2:15-17 - Do not love the world or anything in the world. If anyone loves the world, love for the Father is not in them. 16 For everything in the world—the lust of the flesh, the lust of the eyes, and the pride of life—comes not from the Father but from the world. 17 The world and its desires pass away, but whoever does the will of God lives forever.
Here are a few articles from Sam Storms comparing the freedom we have in Christ (liberty) to legalism and licentiousness.
Are those helpful ways of categorizing legalism vs morality? The Lord Jesus grant you wisdom as you seek a Church.