Curtain 1
"Jesus explained the first step in the new birth experience this way: "Except a man be born again, he cannot see the kingdom of God" (John 3:3). 
Notice Christ's words carefully. The first step of the new birth experience results in seeing the kingdom of God. What does this mean?
Hidden behind the white linen curtain surrounding the courtyard sits the tabernacle containing the Holy Place and Most Holy Place.
At this point, you must pass through the first curtain before you can see the tabernacle. When you do pass through this curtain, you find yourself standing directly in front of the altar of burnt offering. This altar represented the sacrificial death of Jesus Christ, the "Lamb of God" (John 1:29), and it lay directly behind the sanctuary's first, eastern-most gate or curtain.
God’s first work in the miracle of salvation is to lead us to accept the sacrificial death of Jesus Christ on our behalf.
Everything hinges on this.
--The tabernacle came fully into view only after going through the outer gate and passing the altar of burnt offering.--Similarly, the kingdom of God remains a hidden mystery until we accept God's gift of life through Jesus Christ.
--This is why Jesus first told Nicodemus, “Except a man be born again, he cannot see the kingdom of God.”
TimRumsey/Fulcrum7