As unknown - As those who are deemed to be of an obscure and ignoble rank in life, unknown to the great, unknown to fame. The idea, I think, is, that they went as strangers, as persons unknown, in preaching the gospel. Yet, though thus unknown they endeavor to commend themselves as the ministers of God. Though among strangers; though having no introduction from the great and the noble, yet they endeavored so to act as to convince the world that they were the ministers of God. This could he done only by a holy life, and by the evidence of the divine approbation which would attend them in their work. And by this, the ministers of religion, if they are faithful, may make themselves known even among those who were strangers, and may live so as to "give no offence." Every minister and every Christian, even when they are "unknown" and when among strangers, should remember their high character as the servants of God, and should so live as to commend the religion which they profess to love, or which they are called on to preach. And yet how often is it that ministers when among strangers seem to feel themselves at liberty to lay aside their ministerial character, and to engage in conversation, and even partake of amusements which they themselves would regard as wholly improper if it were known that they were the ambassadors of God! And how often is it the case that professing Christians when traveling, when among strangers, when in foreign lands, forget their high calling, and conduct in a manner wholly different from what they did when surrounded by Christians; and when restrained by the sentiments and by the eyes of a Christian community!
And yet well known - Our sentiments and our principles are well known. We have no concealments to make. We practice no disguise. We attempt to impose on no one. Though obscure in our origin; though without rank, of wealth, or power, or patronage, to commend ourselves to favor, yet we have succeeded in making ourselves known to the world. Though obscure in our origin, we are not obscure now. Though suspected of dark designs, yet our principles are all well known to the world. No people of the same obscurity of birth ever succeeded in making themselves more extensively known than did the apostles. The world at large became acquainted with them; and by their self-denial, zeal, and success, they extended their reputation around the globe.
As dying - That is, regarded by others as dying. As condemned often to death; exposed to death; in the midst of trials that expose us to death, and that are ordinarily followed by death; see the note on 1-Corinthians 15:31, on the phrase, "I die daily." They passed through so many trials that it might he said that they were constantly dying. "And, behold, we live." Strange as it may seem, we still survive. Through all our trials we are preserved, and though often exposed to death, yet we still live. The idea here is, that in all these trials, and in these exposures to death, they endeavored to commend themselves as the ministers of God. They bore their trials with patience; submitted to these exposures without a complaint; and ascribed their preservation to the interposition of God.
As chastened - The word "chastened" (παιδευόμενοι paideuomenoi) means corrected, "chastised." It is applied to the chastening which God causes by afflictions and calamities; 1-Corinthians 11:32; Revelation 3:19; Hebrews 12:6. It refers here, not to the scourgings to which they were subjected in the synagogues and elsewhere, but to the chastisements which God inflicted; the trials to which he subjected them. And the idea is, that in the midst of these trials, they endeavored to act as became the ministers of God. They bore them with patience. They submitted to them as coming from his hand. They felt that they were right; and they submitted without a complaint.
And not killed - Though severely chastened, yet we are not put to death. We survive them - preserved by the interposition of God.

As unknown - Persons who are to be suspected as harbouring dark designs; persons of neither birth, parentage, nor respectable connections in life;
And yet well known - Proved by our whole conduct to have no such designs, and demonstrated to be holy, upright, and useful, by the whole train of our peregrinations, through which we can be readily traced from place to place; having preached openly, and done nothing in a corner.
As dying - Through continual dangers, fatigues, and persecutions;
And, behold, we live - We are preserved by the mighty power of God in the greatest dangers and deaths.
As chastened - As though we were disobedient children;
And not killed - Though we continue in the very same line of conduct that is supposed to bring on us those chastisements, and which, if it were criminal, would justly expose us to death for incorrigible obstinacy; but our preservation is a proof that we please God.

As unknown, and yet well known,.... Not unknown to Father, Son, and Spirit, or to one another, but to the world; and that not with respect to their outward estate, but their spiritual and eternal state; as that they were the chosen of God, the children of God, and born again; they knew not what a life they lived, or what they lived upon; and as they were unacquainted with their inward troubles, they were strangers to their spiritual joys here, and to what they shall partake of hereafter. Moreover, something more may be intended in this word "unknown"; as that they were not owned, esteemed, and approved of by them, but slighted, despised, hated, and persecuted:
and yet well known; to God the Father, who loved them with an everlasting love, chose them in Christ, gave them to him, made a covenant with him on their account, and sent his Son to redeem them, which knowledge of them is special, eternal, affectionate, approbative, and attended with care of them; well known to Jesus Christ, who knows all that are his, specially, distinctly, perfectly, and that from everlasting, bears a strong affection for them, takes great care of them, indulges them with intimate communion with him, and openly owns and acknowledges them as his own; well known to the Spirit of God, who enlightened and quickened them, regenerated and sanctified them, wrought faith and every other grace in them, witnessed their adoption to them, led them into all truth, filled and furnished them with his gifts, and dwelt in them, and abode with them, as the seal and earnest of their future glory; and were well known to the saints, and one another: they loved each other, delighted in each other's company; they knew each other's experiences, joys, and sorrows, and, in some measure, their hearts, and even their spiritual and eternal estate.
As dying, and behold we live. They were as dying men, having the seeds of mortality in them, being subject to diseases, which bring on death; and especially as they carried about with them the dying of the Lord Jesus, were continually exposed to death, and in danger of it, lived in the views of it, had the sentence of it in themselves, and were appointed to it. And "behold", to admiration "we live"; a natural life, which we have from God, depends upon hint, and is preserved by him amidst a thousand dangers and enemies to which it is exposed; and we live a spiritual life, a life of grace from Christ, a life of faith on him, and communion with him.
As chastened and not killed; "chastened" by men, and chastened by God; not in a way of vindictive wrath, but in a fatherly manner; but "not killed", or put to a corporeal death by our persecutors, who have sought to take away our lives, but have not yet been suffered to do it: or by the Lord, by the means of afflictions, the messengers of death; these sometimes bring very near it, and God chastens by them, but does not as yet give over to death, because our time is not yet come, and our work not yet done.

unknown . . . yet well known--"unknown" in our true character to those who "evil report" of us, "well known" to those who hold us in "good report" (2-Corinthians 6:8). CONYBEARE explains, "Unknown by men, yet acknowledged by God" (1-Corinthians 13:12). Perhaps both God and men (believers) are intended as knowing him (2-Corinthians 5:11; 2-Corinthians 11:6).
dying . . . live-- (2-Corinthians 1:9; 2-Corinthians 4:10-11; 2-Corinthians 11:23). Compare GAUSSEN'S remark, see on 2-Corinthians 6:5. "Behold" calls attention to the fact as something beyond all expectation.
chastened . . . not killed--realizing Psalm 118:18.

As unknown - For the world knoweth us not, as it knew him not. Yet well known - To God, and to those who are the seals of our ministry. As dying, yet behold - Suddenly, unexpectedly, God interposes, and we live.