John 13:35

This verse contains a third argument pressing this duty of mutual love, taken from the necessity thereof as the badge of their profession. For, as all Sects and societies have their badges and observations, whereby they are known & distinguished from others: So Christ hath appointed this mutual love to be the badge whereby his followers may be discerned. Whence learn, 1. As Christ hath disciples in this world, so they serve a master of whom they need not be ashamed: but they may and ought to avow him in well and woe, and look profanity and trouble out of countenance: for, it is supposed here as great honour, that all men know that ye are my disciples. 2. Albeit true Saints should not be ostentative, nor self-seekers: yet as they ought to assure their own hearts of their good condition before God; So they ought, in their station, to shine and appear such as they are; for, it is their duty, by lawful means and right walking, to make all men know that they are Christs disciples. 3. As true mutual love of the brethren is an infallible evidence of regeneration. 1 Joh. 3.10, 14. and 4.7. So this love is the Christians badge whereby they are known to the world, and without which, Christ and men may look upon them as runawayes from their colours, be what they will otherwise; for, By this shall all men know that ye are my disciples, if ye love one another. See 1 Cor. 12.31. with Chap. 13.1, 2, 3, &c.