Maximus,
You seem like a smart fellow but you have JW rationalism imbedded in your brain. You asked for an explanation and here it is:
1) You cannot have all of the answers to Biblical theology. Mysteries can and do exist and this is partly where faith comes in. Rationalists think they can reason out every mystery and nuance of scripture. Salvation does not require this at all!
2) God can only answer why He uses different methods on humanity. My speculation is that He is demonstrating to us that we cannot hope to live as His creation by our own means. He has a plan that was set in eternity, before time even existed (predestination).
3) Each dispensation ends in failure and judgement of mankind. Man continuously falls well short of the mark (free will). This is indeed a demonstration of how far we are from God and why we need to accept His free offer of salvation by grace through faith alone.
4) Our Lord, Jesus recognized this dispensational truth when he addressed the syngogue in Luke 14.16-20, closing the scroll of Isaiah 61, 1,2 in mid-sentence, "This day is the scripture fulfilled in your ears". He left out the last clause of 61.2 (and the day of vengeance of our God) because he knew that it would not be fulfilled until His second coming. He made a dispensational distinction right there! There is no break in the text yet history shows that we have a two thousand year dispensation to prove it exists: the Church Age.
Here are the guidelines for interpreting scripture:
1) Truth that belongs to one dispensation period must not be read into another. We must always ascertain where we are in history when reading a portion of the Bible.
2) Truth that belongs to a past dispensation must not be used to interpret the present dispensation. To do so puts us under law, as the various heretical groups do time after time.
3) The reverse of the second rule is also applied.
4) Truth that belongs to the future must not be applied to the present. Example: To put the church into the tribulation period is a misapplication of scripture. Israel is again the focus of God's efforts during that period.
5) Truth that belongs to one part of the future must not be read into another part. Example: The judgement seat of Christ, the judgement of "all the nations" and the judgement of the "White Throne" are all separate judgements.
This lack of knowledge (Knowing enough to get in trouble but not enough to figure a way out) is why such groups like the RCC, JWs, Mormons, Seventh Day Adventists, Oneness Pentecostals exist.
Distortions of Biblical truth are exactly what this forum promotes.
Rex