There is a reason why John 3:16 and the verses around it are so popular with evangelical Christians that even popular culture has developed an awareness:  it is a very concise explanation of the gospel and it is very good news!  In these verses we are reminded that by our very nature we are apart from God. Yet, God, through the work of Jesus being "lifted up" made a way for us to enter the light of His good favor. The ultimate purpose is so that we can show how wonderful He is!  

There is also a reason that some "progressive" (i.e. heretical) pastors choke on this verse: it's clear that Jesus is described as the only path to God. Anyone promoting reconciliation with God apart from faith in Jesus is simply wrong.

Moses asked to see God and the only safe thing he could see was God's back. John (and other witnesses) saw what Moses couldn't: God, in the flesh, bringing us grace upon grace.

Moses asked to see God and the only safe thing he could see was God's back. John (and other witnesses) saw what Moses couldn't: God, in the flesh, bringing us grace upon grace.