Summary

Julius Africanus Ante-Nicene Fathers Vol. VI, Extant Fragments of the Chronography… (1885)

And from the capture of Jerusalem that makes 185 years. And at that time King Artaxerxes gave order that the city should be built; and Nehemiah being despatched, superintended the work, and the street and the surrounding wall were built, as had been prophesied. And reckoning from that point, we make up seventy weeks to the time of Christ. For if we begin to reckon from any other point, and not from this, the periods will not correspond, and very many odd results will meet us.
Source: Wikisource

Julius Africanus Ante-Nicene Fathers Vol. VI, Extant Fragments of the Chronography… (1885)

For we find the sovereignty of the Persians comprising a period of 230 years, and that of the Macedonians extending over 370 years, and from that to the 16th [2] year of Tiberius Cæsar is a period of about 60 years.
3. It is by calculating from Artaxerxes, therefore, up to the time of Christ that the seventy weeks are made up, according to the numeration of the Jews.
Source: Wikisource

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