By using the word ‘even’, the KJV implies that Jesus Christ is the same person as ‘him that is true’, but John teaches that Christ has come to show us the Father, and he is not identifying the Father with the Son – ‘his Son’ means the Father’s Son. The words ‘…in his Son Jesus Christ’ tells us the means by which ‘we are in him that is true’.
Arius the great heretic of the early church argued that ‘This is the true God’ refers to the Father, not the Son, but his view must be rejected because:
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the word ‘This’ refers back to the closest previous person which is Christ;
that interpretation would make John repeat himself for no reason at the climax of his epistle – ‘… him that is true … is the true God’ – which is not worth saying since no one would dispute it;
the title ‘eternal life’ is not given by John to the Father, but only to the Son (1 John 1:2; John 1:4; 11:25; 14:26). John 17:3 speaks of knowing a person, not of the person himself.
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