Parallel
Romans 8:16
Robinson-Pierpont Byzantine Textform · Berean Standard Bible
Αὐτὸ τὸ πνεῦμα συμμαρτυρεῖ τῷ πνεύματι ἡμῶν, ὅτι ἐσμὲν τέκνα θεοῦ·
The Spirit Himself testifies with our spirit that we are God’s children.