Biblical "hope" is not wistful and uncertain as is the American English "hope".We have a HOPE of salvation and will not know we are saved until the end.
Jesus said: Those that endure till the end will be saved.
Look again at the passage. We know, said the apostle. Do you know that when you see Jesus you will be like Him? Do you know this?
Those who have this hope (expectation based on faith) are those who purify themselves.
So again, do you know as a fact that you will be like Jesus when you see Him?
1 John 3:1-3 KJV
1) Behold, what manner of love the Father hath bestowed upon us, that we should be called the sons of God: therefore the world knoweth us not, because it knew him not.
2) Beloved, now are we the sons of God, and it doth not yet appear what we shall be: but we know that, when he shall appear, we shall be like him; for we shall see him as he is.
3) And every man that hath this hope in him purifieth himself, even as he is pure.
Do you know?
Much love!