Charles Ellicott Commentary Revelation 3:4

"But thou hast a few names in Sardis that did not defile their garments: and they shall walk with me in white; for they are worthy." — Revelation 3:4 (ASV)

The best manuscripts begin this verse with “But,” or “Nevertheless.” The case of the church in Sardis was bad, yet the loving eyes of the faithful witness would not ignore the good. There were a few who had not defiled their garments. These had not succumbed to the oppressive moral atmosphere around them. The words cannot, of course, be understood of absolute purity. Their praise is that, in the deathlike, self-complacent lethargy around, they had remained earnest in the pursuit of holiness and had not forgotten Him who could cleanse and revive .

They shall walk with me in white.—This white is not the white of the undefiled robe; it is the lustrous white of glory, as in the promise in the following verse .