John Wesley on 1 Samuel 10:5

Prophets - By prophets he understands persons that wholly devoted themselves to religious studies and exercises. For the term of prophesying is not only given to the most eminent act of it, foretelling things to come; but also to preaching, and to the making or singing of psalms, or songs of praise to God. And they that wholly attended upon these things, are called sons of the prophets, who were commonly combined into companies or colleges, that they might more conveniently assist one another in God's work. This institution God was pleased so far to honour and bless, that sometimes he communicated unto those persons the knowledge of future things. Psaltery - Such instruments of musick being then used by prophets and other persons, for the excitation of their spirits in God's service. Prophesy - Either sing God's praises, or speak of the things of God, by a peculiar impulse of his spirit.