John 3:6

3:6 What is born of the flesh is flesh, ¹  and what is born of the Spirit is spirit.

John 6:66

Peter’s Confession

6:66 After this many of his disciples quit following him ²  and did not accompany him ³  any longer.

John 17:15

17:15 I am not asking you to take them out of the world, but that you keep them safe ⁴  from the evil one. ⁵ 

[3:6]  ¹ sn What is born of the flesh is flesh, i.e., what is born of physical heritage is physical. (It is interesting to compare this terminology with that of the dialogue in John 4, especially 4:23, 24.) For John the “flesh” (σάρξ, sarx) emphasizes merely the weakness and mortality of the creature – a neutral term, not necessarily sinful as in Paul. This is confirmed by the reference in John 1:14 to the Logos becoming “flesh.” The author avoids associating sinfulness with the incarnate Christ.

[6:66]  ² tn Grk “many of his disciples went back to what lay behind.”

[6:66]  ³ tn Grk “were not walking with him.”

[17:15]  ³ tn Or “that you protect them”; Grk “that you keep them.”

[17:15]  ⁴ tn The phrase “the evil one” is a reference to Satan. The genitive noun τοῦ πονηροῦ (tou ponhrou) is ambiguous with regard to gender: It may represent the neuter τὸ πονηρόν (to ponhron), “that which is evil,” or the masculine ὁ πονηρός (Jo ponhro"), “the evil one,” i.e., Satan. In view of the frequent use of the masculine in 1 John 2:13-14, 3:12, and 5:18-19 it seems much more probable that the masculine is to be understood here, and that Jesus is praying for his disciples to be protected from Satan. Cf. BDAG 851 s.v. πονηρός 1.b.β and 1.b.γ.