New Revised Standard Version
No one who abides in him sins; no one who sins has either seen him or known him.

Contemporary English Version
and people who stay one in their hearts with him won't keep on sinning. If they do keep on sinning, they don't know Christ, and they have never seen him.

New American Bible
No one who remains in him sins; no one who sins has seen him or known him.

Douay-Rheims Bible
Whosoever abideth in him sinneth not: and whosoever sinneth hath not seen him nor known him.

Whosoever abideth in him sinneth not: and whosoever sinneth hath not seen him nor known him.

abideth.

1 John 2:28 And now, little children, abide in him, that when he shall appear we may have confidence and not be confounded by him at his coming.

John 15:4-7 Abide in me: and I in you. As the branch cannot bear fruit of itself, unless it abide in the vine, so neither can you, unless you abide in me. . . .

whosoever.

1 John 3:2,9 Dearly beloved, we are now the sons of God: and it hath not yet appeared what we shall be. We know that when he shall appear we shall be like to him: because we shall see him as he is. . . .

1 John 2:4 He who saith that he knoweth him and keepeth not his commandments is a liar: and the truth is not in him.

1 John 4:8 He that loveth not knoweth not God: for God is charity.

1 John 5:18 We know that whosoever is born of God sinneth not: but the generation of God preserveth him and the wicked one toucheth him not.

2 Corinthians 3:18 But we all, beholding the glory of the Lord with open face, are transformed into the same image from glory to glory, as by the Spirit of the Lord.

2 Corinthians 4:6 For God, who commanded the light to shine out of darkness, hath shined in our hearts, to give the light of the knowledge of the glory of God, in the face of Christ Jesus.

3 John 1:11 Dearly beloved, follow not that which is evil: but that which is good. He that doth good is of God: he that doth evil hath not seen God.