Revelation 3:3-5

3Remember therefore how thou hast received and heard, and hold fast, and repent. If therefore thou shalt not watch, I will come on thee as a thief, and thou shalt not know what hour I will come upon thee.

4Thou hast a few names even in Sardis which have not defiled their garments; and they shall walk with me in white: for they are worthy.

5He that overcometh, the same shall be clothed in white raiment; and I will not blot out his name out of the book of life, but I will confess his name before my Father, and before his angels.