Whose voice is suggested by the sounds of water and thunder?

Earlier Scripture has attributed an important role to the roar of many waters and to the sound of loud thunder. Ezekiel had mentioned that the sound of many waters was like the sound of the Almighty (Ezekiel 1:24) and elsewhere that the sound of [God’s] coming was like the sound of many waters (Ezekiel 43:2). In fact, John himself had used the phrase roar of many waters to describe the voice of the Son of man whom he saw in Revelation 1 (Revelation 1:15). Again, earlier Scripture speak of thunders when God approached (Exodus 19:16, Exodus 19:19; Psalm 29:3). Though we are not told explicitly whose voice John hears from heaven, the implicit significance of the comparatives points us to God himself. The picture would be that God rejoices over the perseverance of the saints implicit in the 144,000 accompanying the Lamb standing on Mount Zion (Zephaniah 3:17; Isaiah 62:5).