John 15:15 - Matthew Poole's English Annotations on the Holy Bible

By his saying, I call you not servants, he doth not discharge them of that duty and service which they owed to him; for in pressing them to obey his commandments, he declares that duty they owed to him; he only showeth that they were no ordinary servants, but taken into a state of dignity, favour, and familiarity, beyond that of servants, and that he had not treated them like servants, but like intimate, familiar friends. For look as ordinary masters in the world communicate their counsels and whole heart to their friends, especially in things which are of any concern, or may be of any advantage for them to know and understand; whereas they keep themselves at a distance from servants, and they only know so much of their minds as is by them to be done in their masters service: so he had not only revealed to them their duty, what was to be by them done in his service, but had been more free, giving to them to know the mysteries of the kingdom of heaven, as he told them, Matthew 13:11; as well telling them his Father's counsels on the behalf of them, and whatsoever he might communicate to them, as his Father's will, what he would have them to do in obedience to his commandments.