No, I've been saying you CAN know that you are saved and have eternal life! You know it by if you are continuing to sin or not. John said so.
John said the one who is born again does not commit sin. Period. Simple statement.
John's Greek is very simple. That's why they tend to start Koine Greek student with reading and translating John.
What did John actually say about how we know?
1 John 1:6
If we say that we have fellowship with him, and walk in darkness, we lie, and do not the truth:
1 John 2:9-11
9) He that saith he is in the light, and hateth his brother, is in darkness even until now.
10) He that loveth his brother abideth in the light, and there is none occasion of stumbling in him.
11) But he that hateth his brother is in darkness, and walketh in darkness, and knoweth not whither he goeth, because that darkness hath blinded his eyes.
This part . . .
1 John 3:9-10
9) Whosoever is born of God doth not commit sin; for his seed remaineth in him: and he cannot sin, because he is born of God.
10) In this the children of God are manifest, and the children of the devil: whosoever doeth not righteousness is not of God, neither he that loveth not his brother.
This is descriptive, this is how
others know we're born of God. This is looking from the outside in.
How do we know??
1 John 3:16
Hereby perceive we the love of God, because he laid down his life for us: and we ought to lay down our lives for the brethren.
We know He loves us, because He died for us.
1 John 3:18-19
18) My little children, let us not love in word, neither in tongue; but in deed and in truth.
19) And hereby we know that we are of the truth, and shall assure our hearts before him.
And we know we are of the truth if we love, in deed and truth.
Not, count your sins, test your determination, your power of the will, your opinions of your self-control.
Do you love others?
I've heard so many times, "Well, love will be shown by keeping the 10 commandments".
The love that shows to us that we are of the truth is something inside us, the genuine concern and desire for the wellbeing of others. The genuine desire and motions to give ourselves to others, to care for them, to improve their lives, their reward, their fruitfulness.
It's an entirely different way of looking at things.
Much love!