ἐὰν εἰδῆτε ὅτι δίκαιός ἐστι, γινώσκετε ὅτι πᾶς ὁ ποιῶν τὴν δικαιοσύνην ἐξ αὐτοῦ γεγέννηται.

1. ἐὰν
   if
2. εἰδῆτε
   you may know
3. ὅτι
   that
   because
4. δίκαιός
   righteous
   just
5. ἐστι
   is
6.  
   ,
    
7. γινώσκετε
   you know
   know
8. ὅτι
   that
   because
9. πᾶς
   all
   every
10. ὁ
    the
11. ποιῶν
    doing
    making
12. τὴν
    the
13. δικαιοσύνην
    righteousness
    justice
14. ἐξ
    from
    out of
15. αὐτοῦ
    his
16. γεγέννηται
    has been born
17.  
    .
     

If you know that he is righteous, you know that everyone doing righteousness has been born from him.