Everyone who ever lived was “of” flesh, even Jesus. There is a verse in the bible “I, myself”, also in another edition it said “I, OF myself”, and I remember someone telling me that the “trick” was to not be “of yourself”. Paul of course said famously “I am of flesh” but he also was the one who said “I, of myself”.
So I myself or “of” myself is the same as ‘I of my flesh’. It is NOT the same as I “in” my flesh, because the opposite of THAT is “I in the Spirit”. [John said “I was in the Spirit on the Lord’s day”?].
Paul said “those who are in the flesh cannot please God. But you are NOT in the flesh but in the SPIRIT if the Spirit of God dwells in you.”
Jesus was OF flesh but not “IN the flesh”. He was “IN” the Spirit. Paul in Romans 7 was “OF” the flesh but also describing “IN” the flesh. In Romans 8 he mainly describes those who are IN the Spirit, in contrast to those IN the flesh.
Jesus who was of the same flesh as us, (see Hebrews) or “in the likeness of” sinful flesh, was tempted as we are yet without sin. The only difference between us and Jesus with regard to flesh, was that HIS flesh allowed for temptation by desires that originated from His flesh, but that the sin that otherwise would have sprung forth from that enticement, He did not permit to happen. Contrastingly, our flesh which does the same thing as His, is gratified by OUR response which is to give in to that desire and bring forth sin.
So His flesh, unlike ours, never received (or exhibited) any gratification or evidence of its efforts to create sin. Whereas ours does.
HE lived like this consistently. We though, have the opportunity to belong to one of two camps, either to be “IN” the flesh or to be “IN” the Spirit like Him and WITH Him. But we are always “OF” flesh, just as love is always “OF” God.
Jesus at the right time entered IN to his flesh in order to overcome it and repair its sinful nature, to reestablish the divine plan and blueprint that would immortalise His body into eternity by resurrection.