"You have seen for yourselves that I have spoken to you from heaven." — Exodus 20:22
The Israelites were camped at the very mountain where Moses, before joining them in Egypt, had spoken with God at the burning bush (Exodus 3). Now Israel too could see God's fire and hear God's voice through Moses.
Moses had become God's mediator, his chosen spokesman. He brought Israel the news of God's love, God's plans, and God's instructions. Moses represented God, and, on God's behalf, he led Israel to freedom and mission in the Promised Land.
Centuries later, on the mount of transfiguration, the disciples also saw God's fire—in Jesus' face and in his clothing. Jesus' face "shone like the sun, and his clothing became as white as the light" (Matthew 17:1-2). The disciples also heard God's voice there and in Jesus' teachings and, later, through his sacrifice. Jesus is God, and he leads his people to freedom from sin and sends them out to make disciples of all nations.
This message is for each of us as well. I invite you to listen deeply. You can hear God's voice in the words of Scripture, in God's creation around us, and in the worshiping faith community. The Holy Spirit, symbolized in Acts 2 as tongues of fire, helps us to hear God's voice in all of these ways. It's important that we follow God's instructions, and that we obey his words.