G4828–συμμαρτυρέω–summartureō

since they exhibit proof that a knowledge of the conduct which the Law requires is engraven on their hearts, while their consciences also bear witness to the Law, and their thoughts, as if in mutual discussion, accuse them or perhaps maintain their inno

συμμαρτυρούσης summarturousēs “are bearing witness”

The Spirit Himself bears witness, along with our own spirits, to the fact that we are children of God;

συμμαρτυρεῖ summarturei “bears witness with”

I am telling you the truth as a Christian man--it is no falsehood, for my conscience enlightened, as it is, by the Holy Spirit adds its testimony to mine--

συμμαρτυρούσης summarturousēs “while is bearing witness”