Verse 18 is the hinge that closes the libation image of v. 17. Paul has just said that even if he is being poured out as a drink offering on the sacrificial service of the Philippians’ faith, he rejoices and rejoices with them all (χαίρω καὶ συγχαίρω πᾶσιν ὑμῖν). Now he flips the same verb-pair back onto them: τὸ δὲ αὐτὸ καὶ ὑμεῖς χαίρετε καὶ συγχαίρετέ μοι.

Three things carry the verse:

1. τὸ αὐτό is an adverbial accusative — “in the same way,” “with respect to the same thing.” It has no verb of its own; it reaches back and grabs the whole of v. 17.
2. The expressed ὑμεῖς is emphatic. Greek does not need it with a 2pl ending. Paul is turning the sentence around: my joy, now yours.
3. Both verbs are morphologically ambiguous between indicative and imperative. Context makes them imperatives, but the ambiguity is real and should be named rather than hidden.

What the verse is not is a pleasantry. The joy commanded is joy over a possible martyrdom. That is the register the rendering has to keep.

The neuter article + αὐτό in the accusative with no governing verb of its own is a standard adverbial accusative of respect: “as to the same thing,” hence “in the same way / likewise.” BDF treats such neuter accusatives as a settled adverbial idiom (cf. the parallel construction at Matt 27:44, τὸ δʼ αὐτὸ καὶ οἱ λῃσταὶ … ὠνείδιζον αὐτόν, where the same phrase modifies a following verb).

The referent of “the same” is the joy-pair of v. 17, not the libation itself. Paul is not asking the Philippians to be poured out; he is asking them to have the same response to his being poured out that he himself has.

A formal rendering can keep the phrase up front — “And the same thing, you also …” — but the accusative of respect is opaque in English, so the smoothed rendering resolves it to “in the same way,” with the literal wording preserved in the literal tab (§8, culturally opaque idiom).

Both forms are identical in the present active indicative 2pl and the present active imperative 2pl. Nothing in the morphology decides it.

The imperative is adopted in the main renderings. The indicative is preserved as a separate rendering tab rather than buried, since the ambiguity is in the Greek and the reader should see it (§4).

The present aspect in either case is durative/iterative — not “rejoice once,” but “keep rejoicing.” The imperative-forced tab makes that explicit.

συγχαίρω = “rejoice together with,” the σύν- prefix carrying full associative force, construed with the dative (μοι). BDAG gives two senses: (1) to rejoice with someone, share their joy; (2) to congratulate. Sense (1) is right here — Paul is not asking for congratulations on his impending death; he is asking for shared joy in a shared work.

The verb is characteristic of Paul’s body-language for the church (1 Cor 12:26, συγχαίρει πάντα τὰ μέλη — “all the members rejoice together”), and Luke uses it for shared celebration (Luke 1:58; 15:6, 9). The dative μοι is governed by the prefix, an association dative, not an indirect object — “with me,” not “to me.”

Note the chiastic symmetry Paul builds across the two verses: he rejoices and rejoices-with-them (v. 17); they are to rejoice and rejoice-with-him (v. 18). The reciprocity is the point, and the σύν- compound is what carries it. Philippians is saturated with σύν- compounds (σύμψυχοι 2:2, συνεργόν/συστρατιώτην 2:25, συγκοινωνήσαντες 4:14), and this one belongs to that pattern.

Three markers stack up to make this a turn rather than a continuation:

• δέ — postpositive, mildly contrastive here in the sense of “for your part.” Under §10’s epistolary rule the particle is rendered, not dropped; “and” with the following pronominal emphasis carries it.
• καί — adjunctive with the pronoun: “you also.”
• ὑμεῖς — expressed where the verb ending already supplies the subject. In Koine this signals emphasis or contrast (BDF §277). Combined with the adjunctive καί it is doubly marked.

English has no single-word equivalent for a fronted emphatic pronoun, so the modern rendering uses the dash and “you too” to reproduce the contrastive weight.

The startling thing about v. 18 is what Paul asks the Philippians to rejoice about. In v. 17 he has cast his own possible execution in cultic terms: σπένδομαι — he is the drink offering poured out over the sacrifice (θυσία) and priestly service (λειτουργία) of their faith. Verse 18 then commands joy over that.

This is the letter’s cruciform logic applied to Paul himself. The Christ-hymn moved through humiliation to exaltation (2:6–11); Paul’s own self-expenditure is patterned on it, and the appropriate response of the church is not grief but shared joy. The same move stands behind 1:21 (τὸ ζῆν Χριστὸς καὶ τὸ ἀποθανεῖν κέρδος).

The rendering must not soften this. “Be glad about it too” would domesticate a command to rejoice at martyrdom. §5 and Working Principle 6 apply: if the text is hard, the translation stays hard.

Chrysostom (Homilies on Philippians, hom. 8) reads the pair as imperatives and presses the reciprocity: Paul rejoices in being poured out, and demands the same of them, so that they will not mourn what is in fact a crown. Chrysostom is explicit that the joy is joy at martyrdom, and treats Paul’s insistence as pastoral — he is preempting their grief.

Theodoret of Cyrus likewise takes the verbs as commands and glosses τὸ αὐτό as “the same joy,” tying it directly back to the offering imagery of v. 17.

The Latin tradition (Ambrosiaster) reads idipsum autem et vos gaudete et congratulamini mihi, with imperatives, which is how the Vulgate’s gaudete … congratulamini also construes it. So the ancient reading is unanimous for the imperative — worth weighing, since these readers had native or near-native command of the ambiguity.

The verse is textually quiet. NA28 prints τὸ δὲ αὐτὸ καὶ ὑμεῖς χαίρετε καὶ συγχαίρετέ μοι with no variant flagged in the apparatus, and Metzger’s Textual Commentary has no entry on it. Some minuscules read the elided τὸ δʼ αὐτό, a purely orthographic matter with no bearing on sense. No decision here rests on a disputed reading.

The Vulgate — idipsum autem et vos gaudete et congratulamini mihi — renders τὸ αὐτό with the emphatic idipsum (“this very thing”), preserving the adverbial accusative rather than smoothing it, and takes both verbs as imperatives.

The Peshitta uses the ḥdī root for both verbs, with the second in a reciprocal stem plus the preposition, matching the σύν- force of συγχαίρω.

Both ancient versions agree on the imperative and on the associative sense of the compound, which is corroborating (though not decisive) external evidence for the reading adopted.