1.
Unto was used to indicate that something was done or given to someone. (LITERARY or OLD-FASHIONED)
And he said ~ him, ‘Who is my neighbor?’...
I will do ~ others what they did to me.
= to
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2.
Unto was used to indicate that something continued until a particular time. (LITERARY or OLD-FASHIONED)
Be ye faithful ~ the end.
= until
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