These men searched for their family records, but they could not find them and so were excluded from the priesthood as unclean.
Cross References
Nehemiah 7:63And from among the priests: the descendants of Hobaiah, the descendants of Hakkoz, and the descendants of Barzillai (who had married a daughter of Barzillai the Gileadite and was called by their name).
Nehemiah 7:65The governor ordered them not to eat the most holy things until there was a priest to consult the Urim and Thummim.
Treasury of Scripture
These sought their register among those that were reckoned by genealogy, but it was not found: therefore were they, as polluted, put from the priesthood.
These sought
Matthew 22:11-13
And when the king came in to see the guests, he saw there a man which had not on a wedding garment: …
those that were
Nehemiah 7:5
And my God put into mine heart to gather together the nobles, and the rulers, and the people, that they might be reckoned by genealogy. And I found a register of the genealogy of them which came up at the first, and found written therein,
1 Chronicles 9:1
So all Israel were reckoned by genealogies; and, behold, they were written in the book of the kings of Israel and Judah, who were carried away to Babylon for their transgression.
but it was
Matthew 25:11,12
Afterward came also the other virgins, saying, Lord, Lord, open to us…
as polluted
Nehemiah 13:29
Remember them, O my God, because they have defiled the priesthood, and the covenant of the priesthood, and of the Levites.
Leviticus 4:3
If the priest that is anointed do sin according to the sin of the people; then let him bring for his sin, which he hath sinned, a young bullock without blemish unto the LORD for a sin offering.