Romans 8, 14-16 The Holy Spirit himself testifies that we are children of God
14 Ὅσοι γὰρ πνεύματι θεοῦ ἄγονται, οὗτοί εἰσιν υἱοὶ θεοῦ.
14 Indeed, all who are led by the spirit of god, these are sons of god.
15 Οὐ γὰρ ἐλάβετε πνεῦμα δουλείας πάλιν εἰς φόβον, ἀλλ’ ἐλάβετε πνεῦμα υἱοθεσίας, ἐν ᾧ κράζομεν, Ἀββᾶ, ὁ πατήρ.
15 Indeed, you have not received a spirit of bondage once again [that leads] to fear, but you have received a spirit that establishes you as sons, in which we cry Abba, Father.
16 Αὐτὸ τὸ πνεῦμα συμμαρτυρεῖ τῷ πνεύματι ἡμῶν, ὅτι ἐσμὲν τέκνα θεοῦ-
16 This same spirit bears witness, united with our spirit, that we are children of god.
Commentary by Thomas Aquinas on the Epistle to the Romans, Chapter 8, lectio 3, [86201], paragraphs 637.643.645 , on Romans 8:14-16
Deinde cum dicit non enim accepistis, etc., probat propositum scilicet quod spiritum sanctum accipientes sint homines filii Dei.
Then, when he says [Romans 8:15]: “Indeed, you did not receive [a spirit of servitude], etc., he proves his point, i.e. that by receiving the Holy Spirit, men are sons of God.
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643. Et ideo hic dicit: recte dictum est quod qui spiritu Dei aguntur, etc., non enim iterum, in nova lege sicut in veteri lege fuit, accepistis spiritum servitutis in timore, scilicet poenarum, quem timorem spiritus sanctus faciebat; sed accepistis spiritum, scilicet charitatis, qui est adoptionis filiorum, id est, per quem adoptamur in filios Dei. Gal. IV, 5: ut adoptionem filiorum reciperemus. Non autem hoc dicitur quasi sit alius et alius spiritus, sed quia idem est spiritus, scilicet qui in quibusdam facit timorem servilem quasi imperfectum, in aliis facit amorem quasi quoddam perfectum.
And so this one [the apostle Paul] says: “It is rightly said that those who are guided by the spirit of God [these are sons of God].” Indeed, in the new law is not repeated what was in the old law, you then [in the old law] received a spirit of servitude in fear, that is, in fear of punishment, and this fear was engendered [in you] by the Holy Spirit; but [in the new law], you received the spirit, that is, the gratuitous love [of god] which is that of the adoption of sons, that is, through it we are adopted as sons of god. Galatians 4:6 says: “So that we may receive the adoption of sons”. However, this is not said as if there were two different spirits [one in the old law and the other in the new], but since there is only one and the same spirit, it is the same that engenders in some a servile fear almost imperfect, and in others a certain love, almost perfect.
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645. Deinde cum dicit ipse enim spiritus, etc., ostendit idem ex testimonio spiritus sancti, ne forte aliquis dicat, quod in nostra confessione decipimur; unde dicit: ideo dico, quod in spiritu sancto clamamus: abba, pater, ipse enim spiritus testimonium reddit quod sumus filii Dei. Hic autem testimonium reddit non quidem exteriore voce ad aures hominum; sicut pater protestatus est de filio suo, Matth. III, 17, sed reddit testimonium per effectum amoris filialis, quem in nobis facit. Et ideo dicit quod testimonium reddit, non auribus, sed spiritui nostro, et cetera. Act. III, 15: nos testes sumus horum verborum.
Then, when he says that the spirit itself, etc. [in Romans 8:16: “This same spirit bears witness, united with our spirit, that we are children of god.”], he shows the same thing by the witness of the holy spirit, unless, perhaps, someone says that we have erred in the proclamation of our faith. That’s why he goes on to say, “And so I say that in the Holy Spirit we proclaim: abba, father; indeed, it is the Holy Spirit himself who bears witness […] that we are sons of god.” This one, however, does not bear witness through some kind of external voice [that reaches] the ears of men, as when the father declared about his son in Matthew 3:17, but bears witness through the filial love he engenders in us. And that is why he says that [the spirit] bears witness not [audibly] to our ears, but to our spirit, etc. And Acts 3:15 says: “We are witnesses of these words.
In these explanations, Thomas also quotes Jeremiah 3:19, where God speaks to his people through the voice of the prophet Jeremiah:
(וְאָנֹכִי אָמַרְתִּי, אֵיךְ אֲשִׁיתֵךְ בַּבָּנִים, וְאֶתֶּן-לָךְ אֶרֶץ חֶמְדָּה, נַחֲלַת צְבִי צִבְאוֹת גּוֹיִם; וָאֹמַר, אָבִי תקראו- (תִּקְרְאִי-) לִי, וּמֵאַחֲרַי, לֹא תשובו (תָשׁוּבִי
And I said, “How will I place you among the sons and will I give you for your possession [inheritance] a desirable land, beauty of the beauties of peoples”; and he said, “You will call me [variant 2nd person singular: you will call me] my father, and after this you will not turn away [variant 2nd person singular: you will not turn away].”
This article is related to We are God’s children, not his servants, and also to the article that talks about the filial relationship.