Peter both saw and heard the Word of God. Being taken in a trance (a vision while awake), He also heard the Lord speaking to Him. The spoken Word of God to the ear or heart is often referred to as the rhema word of God.  However, God will also speak to us through the written Word, known as the logos word of God. In fact, every rhema word of God has its roots in the logos. In other words, anything God speaks to the ear, will have its roots in the holy scriptures. This is why we are commanded to judge prophecy (1 Cor 14:29).