You asked: Yes but can you date Adam and Jesus from just the bible?
Of course not.
The following comments are those made on this subject by Carl Olof Jonsson, the author of The Gentile Times Reconsidered.
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There are no absolute dates in the Bible. It is nowhere stated, for instance, that Jesus was baptized in 29 A.D., that Cyrus captured Babylon in 539 B.C., or that Jerusalem was desolated in 607 B.C. as the Witnesses claim. The Bible gives relative datings only.
Thus, when we read about the desolation of Jerusalem in 2 Kings 25:1-12, we find only the information that this event took place in the "eleventh year of King Zedekiah" (verse 2), which corresponded to the "nineteenth year of King Nebuchadnezzar the king of Babylon" (verse 8). But when was that? How far from our own time was it? How many years before the Christian Era did it happen? The fact is that the Bible itself gives no information whatsoever that links up this dating with our Christian era.
The books of Kings and Chronicles tell about the kings who ruled in Israel and Judah from Saul, the first king, to Zedekiah, the last one. We are told who succeeded whom and for how many years they ruled. By summing up the lengths of reign from Saul to Zedekiah we can measure the approximate space of time (there are many uncertain points) between these two kings. In this way we find that the period of the Hebrew monarchies covered roughly about 500 years. But still we have found no answer to the question, When on the stream of time did this period start and end?
If the Bible had gone on to give a continous and unbroken series of regnal years from Zedekiah all the way up to the beginning of the Christian Era, the question would have been answered. But Zedekiah was the last king. Nor does the Bible give any other information that helps us calculate the length of the period from Zedekiah's "eleventh year" to the beginning of the Christian Era. Thus we have a period of roughly 500 years, the period of the Hebrew monarchies, but we are not told how far from our time this period was and how it can be fixed to our Christian Era.
If the Bible had preserved dated and detailed descriptions of astronomical events, such as solar and lunar eclipses, or the positions of the planets in relation to different stars and constellations, this would have helped us. Modern astronomers, with their knowledge of the regular movements of the moon and the planets, are able to calculate the positions these heavenly bodies held on the starry sky thousands of years ago. But unfortunately, the Bible provides no information of this kind.
The Bible itself, then, does not show how its chronological datings may be connected with our own era. A chronology that in this manner is "hanging in the air" is only a relative chronology. Only if the Bible had given us the exact distance from the time of Zedekiah up to our own era, either by the aid of a complete and coherent line of lengths of reign, or by detailed and dated astronomical observations, we would have had an absolute chronology, that is, a chronology that gives us the exact distance from the last year of Zedekiah to our own time.
The relative nature of the Biblical dates does not make it impossible to date events mentioned in the Bible. If it were possible to synchronize the chronology of the Bible with the chronology of another country, which in turn can be fixed to our Christian era, then it would be possible to change the relative chronology of the Bible into an absolute chronology. This means, however, that we would have to rely on extra Biblical, that is, secular historical sources, in order to date events in the Bible.
And we have no other choice. If we want to know when an event mentioned in the Bible took place, be it the date for the fall of Babylon, the date for the desolation of Jerusalem by Nebuchadnezzar, the date for the rebuilding of the temple in the reign of Darius I, or any other date whatever, then we have to go to the secular historical sources. This is the grim fact every Bible believer has to accept, whether he or she likes it or not. The simple truth is that without secular sources there is no Bible chronology, no datings of Biblical events.