1. Acts 2:30 (ESV)
  2. Exposition

Why does Peter call David a prophet?

Acts 2:30 (ESV)

30 Being therefore a prophet, and knowing that God had sworn with an oath to him that he would set one of his descendants on his throne,

Though David was a king, he is called a prophet on account of the fact that he composed many of the psalms and the Holy Spirit spoke through him (Acts 1:16).