The anticipated ecstasy of hymns, the crystal sea pictures the absolute, transparent holiness of God. Solomon was commissioned to reflect the pattern in the sea of his temple, provided for the cleansing of the priesthood. In this solid sea of glass, washing from sin and defilement is eternally out of the question. Nothing that defiles can enter into the dwelling place of God. Access to God's Heaven has as it's requirement holiness. It is a condition of entry and not a consequence. Absolute purity, the kind of righteousness that only Jesus Christ can provide, purchased by His blood and freely given to those willing to receive salvation by faith alone.   

This crystal sea marks the boundary conditions of heaven. It is both heaven's floor and earth's ceiling. It is the extent of man's experience of the Divine when sought without Christ; a barrier of solid holiness.   
Revelation chapter 5 paints a picture of the character and nature of the God of heaven:  

Lion like in His Sovereignty  
Calf like in His salvation  
Man like in His incarnation  
Eagle like in the transcendence of His Spirit  

Get a glimpse of Glory  
Get a glimpse of God 

From a series of messages presented at Faskally House Family Week 2022 by Dr J Stewart Gillespie on the theme: 

"Tell me There's a Heaven" 

It has taken 4000 years for the Spirit of God to introduce us to heaven. Heaven is a place of many surprises, but perhaps the greatest of all surprises is that there are so few surprises! Heaven has a door; a door we know of well from John's gospel. Heaven opens with a voice familiar; that of Jesus Christ. Heaven is the throne room of God. Upon the throne of heaven we see one like a Jasper and Sardine stone; one who is the Son of God's right hand and the Son of His mother's sorrow. The throne is surrounded by a rainbow of covenant keeping glory; echoing the one who is life and light. Here is heaven. Here is the God of heaven. This is the God we know. This is Jesus Christ.

The first of 6 studies in the book of Revelation presented at Faskally House, families week in 2022, by Dr J Stewart Gillespie.