Matt.17:5 – While he was still speaking, a bright cloud overshadowed them, and behold, a voice from the cloud said, “This is My beloved Son, with whom I am well pleased; listen to Him!”

This passage gives major insight into the working of the Trinity in God’s plan of redemption of fallen man. We see the manifestation of the Father, the Son, and the Holy Spirit all operating in their respective roles. The Father speaks from the cloud and points us to the Son of God. This is what always happens when the Holy Spirit is involved, the Father speaks and the Son is glorified.
In this beautiful passage of scripture that includes Moses and Elijah we are taken back to the time of Moses where the Lord spoke to Moses from the cloud. Moses spent weeks on the mountain alone with God. Where did the Lord speak to Moses from? He spoke to him from the cloud of glory. What is the significance of this? All through the scripture we see the Holy Spirit working in conjunction with the word of God. In creation the Holy Spirit hovered over the void and the Word was spoken to initiate creation. Just as it was with Moses on the mountain, The Word and Spirit in creation, the Holy Spirit was also speaking to the disciples from the cloud on the Mountain of Transfiguration. What did the Lord say? “This is my beloved Son, listen to Him.” This is how the Reformed Expository Commentary describes this passage.

“The cloud alone would have been enough to confirm God’s presence and blessing. But God also spoke. It was his voice, of course, that came from the cloud, and unlike Peter, God knew exactly what he was talking about. He identified Jesus as his Son and Chosen One—the One to whom the disciples must listen. God may have said this partly to encourage Jesus in his preparation for the cross. Just as the Father spoke at the Son’s baptism, so now again at the transfiguration he speaks to confirm the Son’s calling as his chosen servant.”

So if you feel you are just sort of drifting through life without a clear direction or purpose learn to come into the cloud of His presence. This is the place where the Lord will speak clearly into your life. How do you know if these manifestations are from the Lord? The voice will always magnify Jesus.