We find perfect Christian balance in Jesus Christ himself. We are complete in Him, because in Him all fulness dwells (Col 2:9-10). In Jesus we are holy. In Him we will be holy and live holy. We will be changed and different. We will obey His Word. We won’t be ruled by the flesh any more. But we also are free. We are free from the religion of human achievement. We don’t attain spirituality by keeping lists of rules. With live righteous lives in the liberty wherewith Christ has made us free.
A group of false teachers in the Colossae region went around making people feel guilty because they didn’t keep a list of rules not found in Scripture. To them, even if you had received Christ, you weren’t saved if you didn’t keep their pet menu of rituals and regulations and routines. External standards are always tempting. Unconverted phonies can conform to them, so they don’t provide a suitable basis to judge someone’s conversion. Salvation is by grace through faith, but spiritual bullies desire to coerce others into their own criteria for spirituality, causing confusion and doubt to a church.
So Paul tells these churches at Colossae and Laodecia not to restrict themselves solely because of these false teachers that want them to cramp their lifestyles to earn their way to righteousness (v. 16). This contradicted the sufficiency they had in Christ (vv. 9, 10). He wasn’t, by the way, saying to them that they could do whatever they wanted. Colossians 2 isn’t the only passage in the Bible on liberty. There are huge chunks of text on this in Romans, 1 Corinthians, and Galatians as well. For instance, he wasn’t requiring them to jump through the salvation hoops of the Essenes, but in other passages he does tell the church to look out for the welfare of the weaker brother. They didn’t have liberty to sin, to be worldly, to be a stumbling block, to be a bad testimony, to let their good be evil spoken of, to disobey church leadership, or to cause disunity in the church. But he didn’t want them to be bullied by the onerous self-serving dicta of genuine legalists.

Legalism means treating biblical standards of conduct as regulations to be kept by our own power in order to earn God’s favor. In other words legalism will be present wherever a person is trying to be ethical in his own strength, that is, without relying on the merciful help of God in Christ. Simply put, moral behavior that is not from faith is legalism. The legalist is always a very moral person. In fact the majority of moral people are legalists because their so-called Judeo-Christian morality inherited from their forefathers does not grow out of a humble, contrite reliance on the merciful enabling of God. On the contrary, for the legalist, morality serves the same function that immorality does for the antinomian, the free-thinker, the progressive, namely, it serves as an expression of self-reliance and self-assertion. The reason some Pharisees tithed and fasted is the same reason some German university students take off their clothes and lie around naked in the park in downtown Munich. The moral legalist is always the elder brother of the immoral prodigal. They are blood brothers in God’s sight because both reject the sovereign mercy of God in Christ as a means to righteousness and use either morality or immorality as a means of expressing their independence and self-sufficiency and self-determination. And it is clear from the NT that both will result in a tragic loss of eternal life. So the first meaning of legalism is the terrible mistake of treating biblical standards of conduct as regulations to be kept by our own power in order to earn God’s favor. It is a danger we must guard against in our own hearts every day. And please know that my old self is just as prone to it as anyone.
This is the most common brand of legalism practiced today in modern fundamentalism. The erecting of specific requirements of conduct beyond the teaching of Scripture and making adherence to them the means by which a person is qualified for full participation in the local family of God, the church. This is where unbiblical exclusivism arises. There is no getting around the fact that the church does not include everyone. We do exclude people from membership because we believe worship should imply commitment to the lordship of Christ, the head of the church. But exclusion of people from the church should never be taken lightly. It is a very serious matter. Schools and clubs and societies can set up any human regulations they wish in order to keep certain people out and preserve by rule a particular atmosphere. But the church is not man’s institution. It belongs to Christ. He is the head of the body, and he alone should set the entrance requirements. That is very important!
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This is where unbiblical exclusivism arises. I left a church that admittedly and proudly practices a ’separatist’ philosophy when it comes to extra-Biblical matters. There is no getting around the fact that the church does not include everyone. Peter refers to us as a “chosen race, a royal priesthood, a holy nation” ( I Peter 2:9). But exclusion of people from the church should never be taken lightly. It is a very serious matter. Schools and clubs and societies can set up any human regulations they wish in order to keep certain people out and preserve by rule a particular atmosphere. But the church is not man’s institution. It belongs to Christ. He is the head of the body, and he alone should set the entrance requirements.