ISB ~ Matthew 17 v3

Moses and Elijah:Represent the testimony of the Law and the Prophets, respectively (cf. 5:17; 7:12). They are the only OT figures to hear God’s voice atop Mt. Sinai, also called Horeb (Ex 24:18; 1 Kings 19:8-18). They here witness to the surpassing glory of Jesus as the lawgiver and prophet of the New Covenant (cf. Jn 5:39; Rev 11:3-6).