en_tn/1jn/01/02.md

the life was made known

This can be stated in active form. Alternate translation: "God made the eternal life known to us" or "God made us able to know him, who is eternal life" (See: rc://en/ta/man/jit/figs-activepassive)

we have seen it

or "we have seen him"

testify to it

or "we testfiy about him"

the eternal life, which was with the Father, and which has been made known to us

Here, "the eternal life" refers to the one who gives that life, Jesus. Alternate translation: "the one who enables us to live forever, who was with God the Father, and who has been made known to us" (See: rc://en/ta/man/jit/figs-metonymy)

and which has been made known to us

This was when he lived on earth. This can be stated in active form. Alternate translation: "and which the Father has made known to us" or "and who came to live among us" (See: rc://en/ta/man/jit/figs-activepassive)