Here is a diagram that integrate these concepts:
From the Upper Story perspective I proclaim the truth that I was born again 2,000 years ago in the death, resurrection and ascension of Jesus. At the same time I proclaim from the Lower Story perspective that I was born again at age 14 when the Holy Spirit opened the eyes of my heart to receive, in faith, what had been mine all along in Christ, namely, God's unconditional forgiveness, acceptance and adoption of me as his dearly beloved child.
It is vital to note that Jesus (who is God and humanity united in one person) is, in love, sovereignly present in both the Upper Story and Lower Story. He inhabits and thus defines both kairos and kronos time. In Christ there is no dualism, and thus no cause for "two-sphere thinking." It's not "either I was born again 2,000 years ago" -or- "I was born again at age 14." Rather, it is because I was born from above in Christ 2,000 years ago, that when I was enlightened by the Spirit at age 14, what was objectively true for me all along became subjectively true in my personal (14 year old) experience--a personal encounter with Christ, which in my subjective reality (personal experience) continues to grow deeper (thank you Father, Son and Holy Spirit!).
Understand this: Both the objective and the subjective are real and important (God makes them so!). However, our subjective, Lower Story experience is real (meaningful) only because the objective, Upper Story reality, which undergirds it, is true.
For a more detailed discussion of this important topic in an earlier post, click here.