Revelation 3:4

Names. That is, persons (see on Acts 1:15).

Defiled their garments. A figure for moral defilement, into which most of the church at Sardis had fallen. See on Matt. 22:11; cf. Rev. 16:15; cf. on Isa. 63:6.

In white. In contrast with those who have fallen morally, so defiling their “garments,” those who have been true wear “white,” or clean and unstained, garments, a symbol of their purity. This is indicated both by the succeeding remark, “for they are worthy,” and by the use of the same symbol in ch. 7:13, 14. The latter passage makes clear that such righteousness is not their own, but the result of washing their robes white in the blood of the Lamb. They have received the righteousness of Christ.

White garments are also pictured as worn by the inhabitants of heaven (see Dan. 7:9; Rev. 4:4; 6:11; 19:14), and thus, for the saints, figurative of their “spiritual body” (1 Cor. 15:40–44; cf. vs. 51–54).