The mis-understanding of I John 1:8-10 has caused many bad doctrines and even confusion about how one obtains eternal life in any dispensation. Jesus Christ is eternal life and the only way to receive eternal life is by the gift of God placing one into Christ. There are never any works involved.
The confession in I John has nothing to do with personal salvation for anyone. It is a necessity for Israel to receive the blessings of their promises as laid out in Leviticus 26:40-42 and II Chronicles 7:12-16.
It is what Daniel did, what Ezra and the Levites did, what Nehemiah did and also the people of Jerusalem did. It never had anything to do with personal salvation, but blessings on the land.
That is what must happen again for Israel to be blessed.