17 Now they began on the first (day) of the first month to sanctify, and on the eighth day of the month came they to the porch of Yahweh; and they sanctified the house of Yahweh in eight days: and on the sixteenth day of the first month they made an end.
*Minor differences ignored. Grouped by changes, with first version listed as example.
On the first day - "They began on the first day of the first month Nisan." - Targum.
Now they began on the first [day] of the (g) first month to sanctify, and on the eighth day of the month came they to the porch of the LORD: so they sanctified the house of the LORD in eight days; and in the sixteenth day of the first month they made an end.
(g) Which contained part of March and part of April.
Now they began on the first day of the first month to sanctify,.... Either of the reign of King Hezekiah, or rather of the year; the month Ab or Nisan, as the Targum expresses it:
and on the eighth of the month came they to the porch of the Lord; they seem to have begun cleansing the inner part of the temple first, and so came forward until they came to the porch which led into it:
so they sanctified the house of the Lord in eight days; the holy place, and it may be the most holy place, and the court of the priests:
and on the sixteenth day of the first month they made an end; it took them eight days more to cleanse the outward porch, and the buildings and chambers belonging to the temple; according to Jarchi, it required so much time, because Ahaz had framed pictures of idols upon the walls of the temple, which could not be defaced sooner.
The duration of the purification. On the first day of the first month they commenced with the purification of the courts; on the eighth day of the same month they came to the porch of Jahve, and with it began the purification of the temple building. This lasted eight days more, so that the work was finished on the sixteenth day of the first month.
The first day - A happy beginning of the new year! Thus should every year begin with the reformation of what is amiss, and the purging away of all the defilements contracted the foregoing year.
*More commentary available at chapter level.