I am convinced that in all matters of Christian living – be it theological formulation, or practical morality – legalism and liberalism are two sides of the same coin, which is a mindless refusal to act according to wisdom in the Spirit when presented with a genuine “grey area.” It is always easier to turn off your brain and either invent a new rule that is not in the Bible (c.f. 1 Cor 4:6), or throw caution to the wind and say that “anything goes.” It is always more difficult and more Christian to take the narrow road of applying wisdom in the Spirit at all times.
“Who decides where the line is?” asks the liberal, pretending that the cliff of godlessness is no real danger (c.f. Matt 7:21-23; 1 Cor 5:9-13). “That’s a slippery slope,” often warns the legalist, assuming that the opposing gorge of self-impressed, pride-soaked Pharisaical living is not an equally perilous danger (c.f. Matt 15:9; Col 2:20-23).
The narrow road is neither of these. Who decides? We do, as the body of Christ. All of the time; every time. We do so by wisdom in the Spirit, while grace helps us to defy the slippery slopes of life. The Christian is never off-duty. He or she is always mindful that the human heart cannot be trusted without reservation (Jer. 17:9; Prov 14:12; 1 Pet 5:8) and that we must constantly strive to think clearly, carefully, and prayerfully (Prov. 18:13; John 7:24), using wisdom in the Spirit (1 Cor 2:6-16).