The imagery of 'defiled garments' is powerful. What does it mean to keep your spiritual garments clean when the world, and even the church, seems determined to stain them?
The 'garments' here represent more than just outward actions; they symbolize the purity of one's Christian life, profession, and inner spiritual state. In Sardis, a city known for its textile industry and perhaps its moral laxity, the idea of soiled garments would have been readily understood.
These faithful few 'have not defiled their garments.' This doesn't mean they were sinless, but rather that they actively resisted the prevailing corruptions around them. They maintained their integrity, their devotion to Christ, and their commitment to His teachings.