This feature of the problem is sometimes represented by the useful metaphor that the history of the Church just at this period "passes through a tunnel" or "runs underground." We are in the light of day during most of the time covered by the New Testament; and we are again in the light of day directly we reach the time covered by the abundant writings of Irenaeus, Clement of Alexandria, Tertullian, and others. But during the intervening period we are, not indeed in total darkness, but in a passage the obscurity of which is only slightly relieved by an occasional lamp or light-hole. Leaving this tantalizing interval, about which the one thing that is certain is that many certainties are not likely to be found in it, we pass on to look for our two next certainties in the periods which precede and follow it.
3. In the period covered by the New Testament it is certain that the Church had officers who discharged spiritual functions which were not discharged by ordinary Christians; in other words _a distinction was made from the first between clergy and laity_. Of this fact the Pastoral Epistles contain abundant evidence; and further evidence is scattered up and down the New Testament, from the earliest document in the volume to the last. In the First Epistle to the Thessalonians, which is certainly the earliest Christian writing that has come down to us, we find St. Paul beseeching the Church of the Thessalonians "to know them that _labour among you_, and _are over you in the Lord_, and _admonish_ you; and to esteem them exceeding highly in love for their work's sake" (v. 12, 13). The three functions here enumerated are evidently functions to be exercised by a few with regard to the many: they are not duties which every one is to discharge towards every one. In the Third Epistle of St. John, which is certainly one of the latest, and perhaps the very latest, of the writings contained in the New Testament, the incident about Diotrephes seems to show that not only ecclesiastical government, but ecclesiastical government by a single official, was already in existence in the Church in which Diotrephes "loved to have the pre-eminence" (9, 10). In between these two we have the exhortation in the Epistle to the Hebrews: "Obey them that _have the rule over you_ and submit to them: for they watch in behalf of your _souls_, as they that shall give account" (xiii. 17). And directly we go outside the New Testament and look at the Epistle of the Church of Rome to the Church of Corinth, commonly called the First Epistle of Clement, we find the same distinction between clergy and laity observed. In this letter, which almost certainly was written during the lifetime of St. John, we read that the Apostles, "preaching everywhere in country and town, appointed their firstfruits, when they had proved them by the Spirit, to be bishops and deacons unto them that should believe. And this they did in no new fashion; for indeed it had been written concerning bishops and deacons from very ancient times; for thus saith the scripture in a certain place, I will appoint their bishops in righteousness, and their deacons in faith"--the last words being an inaccurate quotation of the LXX. of Isa. lx. 17. And a little further on Clement writes: "Our Apostles knew through our Lord Jesus Christ that there would be strife over the name of the bishop's office. For this cause, therefore, having received complete fore-knowledge, they appointed the aforesaid persons, and afterwards they provided a continuance, that if these should fall asleep, other approved men should succeed to their ministration. Those therefore who were appointed by them, or afterward by other men of repute with the consent of the whole Church, and have ministered unblamably to the flock of Christ in lowliness of mind, peacefully and with all modesty, and for long time have borne a good report with all--these men we consider to be unjustly thrust out from their ministration. For it will be no light sin for us, if we thrust out those who have offered the gifts of the bishop's office unblamably and holily. Blessed are those presbyters who have gone before, seeing that their departure was fruitful and ripe, for they have no fear lest any one should remove them from their appointed place. For we see that ye have displaced certain persons, though they were living honourably, from the ministration which they had kept blamelessly" (xlii., xliv.).