We can’t afford to tolerate a little bit of legalism, because it won’t stay little. Its influence will spread throughout the whole church and infect everything. This isn’t a case of finding the right balance between grace and law. In Mark 8 Jesus warned the disciples to beware the leaven of the Pharisees and the leaven of Herod. The Pharisees worked really hard at keeping all the religious rules as if their acceptance into heaven depended on it, while Herod was the opposite. The leaven of the Pharisees is legalism; the leaven of Herod is license. The solution to one problem isn’t to add a bit of the other. If someone’s legalistic, you obviously don’t try to encourage them to start breaking the law. On the other hand, if someone’s living anti-God’s law, you don’t try to motivate them to change their behaviour by persuading them their standing before God depends on their obedience. Whichever leaven you use will “leaven the whole lump”. We need pure gospel.