"Because God, in this manner, loved the world, He gave His Only Begotten Son, that the ones believing in Him can never perish, but have life eternal."
God gave His Son + God gave me faith to become a believing one = salvation.
Did Nicodemus get saved? Why or why not?
Yes. The question is "when." He made the transition from OT saint to NT saint.
John 6:37 All that the Father giveth me shall come to me; and him that cometh to me I will in no wise cast out.
All of the OT saints, who belonged to the Father, came to Christ and not a single one was lost.
Nicodemus, along with Joseph, claimed the body of Christ and placed it in the tomb. He started out rather weak, coming to Christ under cover of darkness out of fear, but grew into a bold Christian openly standing by the Lord after His crucifixion.
It is interesting that he, a ruler of the Jews, came to Christ to talk, not about the state of affairs of Israel, but the state of his own soul.
As the bible teaches that the natural man can not receive spiritual truth, he cannot know spiritual truth, and he does not seek spiritual truth, I can only assume that Nicodemus, who came seeking spiritual truth, was one of the OT saints making up spiritual Israel who, according to John 6:37, would recognize and come to Christ as Messiah and not a single one of them would be lost.
It is often difficult for early 21st century baptists to understand the transitional nature of the Gospels and the Book of Acts. Moving from the OT economy under the Old Covenant to the New Testament economy under the New Covenant is something we have no experience with. We were born under the New Covenant, and were born again under the New Covenant, so there is no confusion in our experience as was endured by the OT saints making the transition from the Old Covenant to the New Covenant.
It is best to just accept the narrative in John for what it is, a narrative of the transition of one OT saint from the Old to the New Covenant. When we try to over-analyse it and "make it walk on all fours" we increase the level of confusion. This is, of course, the grave danger of "proof texting." We try to make a text say something it was never intended to say. John 3 is not about we who are born and born again under the New Covenant. It is about those who made the transition from the Old to the New. We face no such challenges. And when we try to apply a descriptive narrative as a theological cornerstone we create a serious anachronism.
I remember when I was in seminary one of our assignments was to prepare and preach a sermon to our homiletics class. We, the other students, then graded each students' messages.
One young man preached on "Fire From Heaven" and went on and on about how badly we needed "Fire from Heaven" just like Elijah experienced on Mt. Carmel. When it came time to grade the young brother's sermon I gave him an "F." He was quite upset and demanded an explanation. I told him that God sent fire from heaven to burn up the sacrifice, the wood, the water, and even the stone because He was demonstrating His great power over the prophets of Ashtoreth who worshiped the Sidonian Fire god in the form of lightening coming down from the sky. God was showing that His fire from heaven made the lightening, thought to be from the Sidonian Fire god, pale and puny in comparison. As we don't do battle against those who worship the Sidonian Fire god today no such display is necessary. Today, the evidence of being filled with the Holy Spirit is that we "speak the word of God with boldness" (Acts 4:31).
Remember the very basics of our understanding of the bible is the
Historical-Grammatical hermeneutic. We must understand what we read in the context of what was happening at that time in history. And John 3 is no exception.
Nicodemus accepted what Jesus was teaching him, not in order to be saved, but because he was already a believing part of spiritual Israel.
