“Conduct yourselves worthily of the Gospel of Christ.” Conduct yourselves, πολιτευεσυε, that is, live as citizens. Live as citizens of the Kingdom of Christ ought to live. How is this done? Look to the Gospel. Live as the Gospel of Christ requires.
“The Gospel requires this: ‘If any man would come after Me, let him deny himself, take up his cross, and follow Me’ (cf. Mk 8:34)” (blessed Theophylact).
In this lies the spirit of life in Christ Jesus. “Those who are Christ’s have crucified the flesh with its passions and desires” (cf. Gal 5:24). Strict ascetical life is the seal of evangelical life. Only strict ascetics are true evangelicals.
“That whether I come and see you, or am absent, I may hear of your affairs.” This circumstance is mentioned to stir their zeal, because of their heartfelt bond with the Apostle. Yet it adds nothing to the substance of the instruction.
Like a father to his children, like a beloved teacher to beloved disciples, he says to them: See that you do not become a cause of grief to me. Your progress is exceedingly dear to me. Nothing is so desirable to me as to see and hear that you are perfect in all things.
“Whether I come... or am absent.” “He says this not because he has changed his intention and no longer wishes to come to them, but, if it should happen otherwise, he adds: even when I am absent from you, I can rejoice, if I hear that...” (Chrysostom).
“If” stands for “when.” When I come and see you, or while I have not yet come, while I am preparing to come or am on the road, may I hear of you. May I both see and hear only what is good concerning you.
Showing what good he wishes to see and hear, the holy Apostle returns to the instruction: that you stand in one spirit and with one soul. “In truth” is not in the Greek original.
If this word is accepted, its fitting sense here is this: do not merely appear to stand, but truly stand. Stand sincerely. As you appear to be, so remain also in the heart.
“Stand” points to firmness in faith and in life according to faith. As a pillar deeply set in the ground stands firm and cannot be shaken, so they are firm in conduct worthy of the Gospel.
“In one spirit and with one soul.” “After telling them to conduct themselves worthily of the Gospel, he indicates the form of such conduct. This is sincerity in faith, for one cannot otherwise be in one spirit. Then he commands them also to have one soul, which is proof of very great mutual love” (John of Damascus).
“One spirit and one soul” may be taken without distinction, meaning perfect agreement in all things and loving unity. Or spirit may mean their identical relation to God, while soul means the other manifestations of inner life.
“In one spirit” means that all alike, through faith in the Lord, stand before His face in the heart. All are zealous with the same zeal to appear well-pleasing to Him in everything.
“With one soul” means that they hold the same pattern of thoughts, nourish the same good dispositions, intentions, and undertakings, and have the same tastes in all things.
Both together will form among them a strong bond of love, unconquerable by enemies both outward and inward.
Chrysostom says: “This especially unites the faithful and sustains love. Therefore Christ said, ‘That they may be one’ (Jn 17:11). ‘A kingdom divided against itself will not stand’ (cf. Mt 12:25). Therefore Paul everywhere strongly urges concord. For this same reason Christ says, ‘By this all will know that you are My disciples, if you have love among yourselves’ (Jn 13:35). What does ‘in one spirit’ mean? It means in one and the same gift of concord and zeal. Likewise, to stand with one soul means one-mindedness. In this sense many souls are called one. So it was of old. It is said, ‘They had one heart and one soul’ (cf. Acts 4:32).”
“Striving together for the faith of the Gospel.” “This means: help one another in the struggle for the evangelical faith” (Chrysostom).
The word “voluntarily” is not in the Greek original. If it is accepted, it means willingly, with a firm resolve not to yield, and with a desire to stand firm whatever it may cost.
“The faith of the Gospel,” the evangelical faith, was nowhere established without struggle. Everywhere it met resistance. It appeared amid the world, whose spirit was completely opposed to it, and it drove that spirit from its own circle.
For this reason the world hated it, resisted it, and persecuted it. Therefore every community of believers inevitably had to be engaged in the struggle of self-defense.
For success in this struggle the Apostle commands them to stand in one spirit and with one soul, so that all may be as one soul. Who can overcome such people?
Invincibility does not mean suffering nothing. It means not falling away from the faith, even if one must die.
How much courage the soul breathes in when all strengthen it. Then one soul is as strong as all souls together.
So it is in faith, as the martyrs showed. So it is also in life, as brotherhoods prove when they unite for progress in Christian perfection. Example, counsel, and prayer immediately put every enemy to flight.
THEOSIS