Revelation 4:6
And before the throne there was a sea of glass like unto crystal: and in the midst of the throne, and round about the throne, were four beasts full of eyes before and behind. And before the throne there was a sea of glass like unto crystal: and in the midst of the throne, and round about the throne, were four beasts full of eyes before and behind.
The verse belongs to the vision in which John was shown God's throne and the glories of heaven, as part of symbolic revelations that disclose the experience and history of the church through the end of time and help God's people understand the dangers and conflicts before them. The vision was given by Jesus to John when he was aged, about half a century after Jesus had ascended to present His church before God and to prepare mansions for His faithful ones, because He still loved His people. It shows the throne of God in heaven with anthems of joy resounding through the heavenly courts, opening the glories of heaven to view and revealing God's plan for future ages.
The sea before the throne is calm, placid and still like ocean waters at rest, with varied reflections of light and beauty. This stands in contrast to gale and storm and tossing waves, and to the troubled sea when it cannot rest, which pictures people wasting their lives in vain struggles after happiness. The verse shows worshipers above gathered round about the throne of God in prayer and praise, in the light and glory of God.
When believers assemble together as active workers in meetings for prayer and praise, they come near to those heavenly worshipers. Those who absent themselves from religious services fail to come near, and because their lamps are not trimmed and burning they reflect the light and glory of God only feebly. Seeing the throne stirs longing to stand with the redeemed in the presence of God.
The crystal sea before God's great white throne is the goal that Christians draw nearer with every faithful step, with the Christian race run with patience one day and one step at a time. Reaching that sea and throne comes by giving oneself to Jesus as a poor miserable sinner, repenting and trusting the infinite price He paid on Calvary for salvation. The sea of glass is the place the redeemed reach after ascending with Jesus, where the 144,000 stand together on it. The ascent with Jesus to the sea lasts seven days.
The 144,000 stand there together in a perfect square. There they are clothed in white, in glorious white mantles. There they appear crowned and victorious. Jesus Himself places crowns on their heads and gives them harps and palms of victory. The crowns differ in brightness and number of stars, but all are satisfied with their own. After standing on the sea before entering the city, they march across it to the city's gate and are welcomed into the city.