In John 10, (implicitly) during the Feast of Tabernacles, Jesus famously tells a parable (paroimia) of a shepherd and his flock of sheep in which he curiously identifies himself both as the gate by which the sheep enter the fold, and the "good" shepherd himself, who leads them out to pastures and ironically "saves" them by laying down his "life" (psychē) for their benefit (hyper) (John 10:1-13). Later, at the Feast of Hanukkah, in response to the crowd's request to tell them "plainly" (parrēsiai) whether or not he was the Messiah (10:24), he tells them that he already had done so―and he had indeed, precisely by his claim to be the Davidic Good Shepherd promised in Ezekiel 34 (10:25; see my earlier post here). He then turned the screws by asserting that their (implicit) unbelief was manifestation of their not truly being his sheep, a deliberately offensive response to people whose self-image, as God's covenant people, entailed being God's flock waiting for the promised shepherd.
At this point, Jesus explicitly refers back to the parable and makes some extraordinary theological claims:
My sheep hear my voice. I know them, and they follow me. I give them eternal life, and they will never perish. No one will snatch them out of my hand. What my Father has given me is greater than all else,* and no one can snatch it out of the Father's hand. I and the Father are one. (John 10:27-30, NRSV [alt. JRM]).
This text is significant, both in what it says about the "eternal life" (zōē aiōnios)** given to the sheep by Jesus and in the Christological basis for the confidence he has in that certain future. This "life," secured by virtue of his "laying his own psychē down for them" (John 10:11, 14, 17-18) and "taking it up again" (cf. palin labein autēn, vv. 17-18) in resurrection,*** is ineradicable: as Jesus says, "they will by no means perish … ever" (ou mē apolōntai eis ton aiōna). The use of the double negative with the subjunctive mood here is what Greek grammarians refer to as a "subjunctive of emphatic negation;" what is denied isn't simply the fact of something, but its very possibility of ever happening. Thus the Johannine Jesus plainly asserts that aspect of the Calvinist doctrine of the perseverance/preservation of the saints commonly referred to as "eternal security."****
What is important, however, is the Christology on which this security is based. The foundation of the sheep's security lies in their having been gifted to Jesus by the one he calls his "Father." In this connection, in his original Sukkoth Good Shepherd Discourse, Jesus claims that no one had the ability to take his life from him―hence attempts to do so were foiled because it was not yet his "hour" to die/be exalted (cf. John 7:30, 44; 8:20, 59; 10:39)―because he alone had the authority to both lay down and take his life up again (John 10:18). How so? Because, as he claimed earlier, he had been given "life" (zōē) "in himself" from the Father, the very life the Father possesses (John 5:26). Nevertheless, he would in fact lay his life down in obedience to the Father's will ("I received this commandment from the Father"), because of which the Father "loves" him" (10:17). It is this obedient-yet-willing death that is the basis for the "eternal life" given by Jesus to the sheep gifted to him by the Father. And this is a life they cannot lose, forfeit, or have snatched forcibly (oudeis dynatai harpazein) from them because of the double, invincible grip of the Son and the Father. Indeed, as Jesus concludes his response, "I and my Father are one" (10:30).*****
This text, of course, has been the focus of study and controversy throughout church history. The salient point is that the word "one" (hen) is neuter, not masculine (heis); hence the "oneness" between them denotes a singularity, not of personhood―sorry, Sabellius!―but of authority and operation. Just as Jesus claims an exclusive, reciprocal knowledge of the Father (John 10:15), and, even more outrageously, claims that he and the Father have a mutual indwelling ("perichoresis,"10:38), so, despite an "economic" subordinationism of Jesus to the will of the Father,****** they work together as one in the activity of guarding and protecting the sheep Jesus came to save. In case someone might be inclined to deduce a sort of ontological subordinationism here, note that John certainly didn't intend it this way. As was the case in John 5:18, the "Jews" were incensed and picked up stones to stone him because they rightly understood this as a claim to be God (John 10:32-33).
The title "Son of God" was, of course, in keeping with 2 Samuel 7:14 and (especially) Psalm 2:7, used as an honorific for the king of Israel and the hoped-for Davidic Messiah, both in Second Temple Judaism (cf., from Qumran, 4Q174.1-10) and in the New Testament (e.g., Mark 1:1; Matthew 16:16; Romans 1:3-4). One sees a reflection of this in John's Gospel as well, most notably in the parallelism of Nathanael's initial confession: "You are the son of God; you are the king of Israel" (John 1:49). What stands out in John's Gospel, however, is the stunning absolute use of the title "Son" in conjunction with God being referenced as the "Father." While not entirely absent in the Synoptic tradition, most notably the so-called "Johannine thunderbolt" found in the Q tradition recorded in Matthew 11:27//Luke 10:22, the absolute "Son" recurs repeatedly in John.******* Moreover, he is famously called God's "one and only" or "unique" (monogenēs) Son in John 3:16, and simply "monogenēs" in apposition to the noun theos (hence, "The one and only, himself God")******** in John 1:18.
This last text points to the key to understanding John's Father-Son dynamic. Simply stated, John's Christology must be understood under the controlling rubric of the Prologue's Logos ("Word") Christology (John 1:1-18). Jesus, throughout the Gospel, is to be understood by the reader as the incarnate "Word," the one who was himself God by nature and therefore existed "in the beginning" with God and was the instrument through which the universe came into being. His incarnation marked the fulfillment of the promise of a new Temple, the eschatological "meeting place" between God and humanity where God's glory is made visible. As the "one and only one/Son" he is the very self-expression of the invisible God (cf. Colossians 1:15). Thus understood, Jesus' identification as "the Son" simpliciter is, in the words of James D. G. Dunn, "an elaboration of the initial explicit identification of Jesus as the incarnate Wisdom/Logos―an identification taken over certainly from earlier Christian tradition, but expounded in John's distinctive fashion."*********
It is as the Incarnate Word that Jesus the Son, the uttered Logos, both reveals the Father and works with him to secure and guarantee the ultimate salvation of the sheep the Father had entrusted to his care. That is where our security lies. Soli Deo Gloria!

