I think the proper way to interpret this verse is to consider it in context, as with most parts of the Bible. 1 John was written about 100 AD, and at the time it was written the community was split, people had left the Church, and John was writing to encourage members to stay faithful.
So this verse is really contrasting God and his people to the opponents. 1 John 1:6-2:2 is composed of six “if, then” statements. Three expose the errors of the opponents by quoting their slogans, characterizing their way of life, and asserting the consequences of their inconsistency. Since the author three times repeats the formula, “if we say . . .”, the opponents and perhaps some who remained within the community were apparently making assertions like: “we have fellowship with him”; “we have no sin”; and “we have never sinned”. Those who live in sin cannot claim fellowship with God, however, because he is light.%between%
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