New birth is one of the key topics in John 3. Nicodemus recognizes Jesus’ signs and teachings as unmistakable evidence of his divine origin so Nicodemus politely invites Jesus to expound His teaching.
He is taught that the Kingdom of God belongs to the realm of the Spirit and to see this kingdom, spiritual regeneration is a necessity. Human integrity or ability cannot achieve this state which is essentially heavenly, “born from above,” made possible through the Spirit of God. The whole process of spiritual regeneration is the product of God’s deep love for the world.
Jn 3:16 For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life.