PULPIT COMMENTARY :
“Verse 16. – So the last, etc. The parable concludes with the saying with which it began (Matthew 19:30), but with some inversion in the order of the words. There it was, “Many first shall be last; and last first;” here it is, The last shall be first, and the first last. The circumstances of the parable necessitate this change. The last called were first paid, and were equal to the first in recompense; the first were behind the others in time of payment, and in the spirit with which they received their wages; they were also treated with less generosity than the others. For many be called…chosen (Matthew 22:14). This clause is omitted by א, B, and other manuscripts; but it has good authority, and is most probably genuine. It is added in explanation or justification of the preceding statement. From not seeing its applicability, and regarding it as opposing the intention of the parable, some transcribers and some editors have expunged it from the text. But it would seem that Christ takes occasion from the particular case in the parable to make a general statement, that not all who are called would receive reward; because many would not answer the call, or would nullify it by their conduct; not, as Theophylact says, that salvation is limited, but men’s efforts to obtain it are feeble or negative. In other words, many outwardly members of the kingdom of God are unworthy of, and shall not share in, its spiritual blessings. Chosen. Many, that is virtually all, are chosen; but there is an election within the election, and they only who are of this inner circle shall be recompensed at the resurrection of the just. The interpretation of the parable. – As in all parables, so here, we are to regard the general scope, and not lay too much stress on details, which often, while adding to the vividness of the picture, contribute nothing to its spiritual side. The explanation of this difficult parable has greatly exercised the minds of commentators in all ages of the Church, and various have been the views with which its bearing has been regarded. We may, however, select two expositions which seem to embody most of the suggestions advanced, and are in themselves most reasonable. The first considers it as of individual application – the call of God coming to the soul at different ages of life. Thus the householder is God, the marketplace the world, the vineyard the visible Church, the labourers are men who have to do their work therein, the steward is Christ, who superintends and rewards the faithful workers. The hours of the day represent the various periods of men’s life at which they hear and answer God’s call to a closer walk with him, when, as modern theology terms it, they are converted. Some, at the first hour, from their very infancy, live a pure and holy life; some at the third hour, in early youth, begin to serve God effectually; others at midday, in full maturity; others at the ninth hour, when old age is creeping on them; and lastly others obey the call only at the eleventh hour, at the very approach of death. And all who have laboured at all, without regard to the length of service, receive the “penny,” i.e. not some indefinite temporal benefit, but eternal life, which in a general sense (without considering the difference of degrees which shall exist) is the same for all. The apparent unfairness of this recompense, if we take a merely human view of the transaction, is obvious. They who have lived a life of holiness, and they who have given to God only the dregs of their ill-spent days, receive the same salvation. The difficulty is removed in two ways. We may say that the capacity for receiving and enjoying the reward depends ca the recipient, and that what to one would be infinite bliss and satisfaction, to another would offer far inferior enjoyment. Or we may take refuge in the mysteriousness of God’s arrangements, and hold that the considerations in accordance with which God apportions his rewards are known only to him, and are truly, and are intended to be, beyond human understanding. Further, if the hours represent the stages of human life at which Christians are called, surely, to make the parable concinnous, they ought to be the same persons who are invited on each occasion, not different ones. We should be told, not that the householder found others wanting work, and sent all thus found into the vineyard; but that some of those called at the various hours refused the work and scoffed at his offer, while others after a time accepted it, and at the approach of the night all the idle remnant consented to labour, thankful at last to win wages for little trouble. But the parable says nothing of all this, and would need much alteration to make it speak so. There is another difficulty which has to be met, if the above interpretation is adopted. How are we to explain the murmuring of the discontented labourers? There can be no envy and displeasure in heaven. It is not conceivable that any who have obtained the gift of eternal life should be dissatisfied with their reward or jealous of others. This is not a mere accessory which is outside the spirit of the story, and adds no item to its mystical signification; it is really the leading feature, and the householder’s own interference and reproof are based entirely on this behaviour of the first called. If the “penny” signifies eternal life, and the labourers are all the called, there is no satisfactory explanation of this part of the parable. The murmur is heard after the reception of the reward, and is censured accordingly; these things could not be found in the Church triumphant; none can murmur there; if they did feel envy and discontent, they would not be worthy of a place in the kingdom. Therefore another interpretation must be advanced which will allow the proper importance to this detail of the parable. The only one that does this is that which gives a national, not simply an individual, bearing to the story. According to this exposition, it applies to the calling of the Jews and the Gentiles, though there are still particulars which do not entirely or without some violence suit the application. The “penny” which all receive is the favour of God, the privileges that crown and reward the members of his kingdom. God’s ancient people were first called to work in his vineyard. The various hours of the day cannot be accurately explained. Many interpreters follow St. Gregory in defining the first hour as extending from Adam to Noah, the third from Noah to Abraham, the sixth from Abraham to Moses, the ninth from Moses to the coming of Christ, the eleventh from the coming of Christ to the end of the world. During all the day, up to the eleventh hour, the call was confined to the Jews and their progenitors; in the eleventh hour the Gentiles are called, and, accepting the call, receive the same privileges as the Jews. It is better to forego any attempt to interpret the various hours and the various sets of labourers definitely, except to observe that the first called, with whom a covenant was made, plainly represent the Jews, the people called under the covenant of works, who were to be rewarded according to their service; the other workers are not paid stipulated wages; they receive (“I will give”) reward of free grace in accordance with God’s inscrutable appointment. That the Jews murmured at the admission of the Gentiles to the kingdom of God and the Father’s favour, we are taught in many places. The discontent of the elder brother in the parable of the prodigal son is a case in point. So in Acts 13:45, 46, the Jews are filled with envy that the Word should be spoken to and accepted by heathens, and St. Paul (1 Thessalonians 2:16) complains that the Jews forbade him and his fellow apostles “to speak to the Gentiles, that they might be saved.” Our Lord looks forward to and prepares his disciples for this envious and ungenerous behaviour, as he continually teaches that the gospel is for all men everywhere, confined to no people or country, but free as the air of heaven or the light of the all-fostering sun. These Gentiles are the last in time, but by their willing service and obedience in the faith are made first; while God’s ancient people, once the first, become by their jealousy and hatred of others the last. “There (ἐκεῖ) shall be weeping and gnashing of teeth, when ye shall see Abraham, and Isaac, and Jacob, and all the prophets, in the kingdom of God, and you yourselves thrust out. And they shall come from the east, and from the west, and from the north, and from the south, and shall sit down in the kingdom of God” (Luke 13:28, 29). This momentous change in the relation of the peculiar people to the rest of the world was thus foretold and prepared for. And the lesson ends with the mournful fact, read by the eye of the Omniscient, that though virtually all the Jews were called, yet but a small remnant will accept the gospel – the elect of grace, a little flock. By this parable, regarded in its primary application as a reply to Peter’s question (Matthew 19:27), “What shall we have therefore?” the apostles are warned that they are not to expect as their due something supereminent over those called later than themselves; that the reward is not of merit, but of free grace. This last thought pervades the whole similitude, and must be borne carefully in mind, whether we take the individual, or the national, or any other mixed interpretation. ”
-Pulpit Commentary

Link:
http://biblehub.com/matthew/20-16.htm

NICEA HISTORY:
Their neutrality rapidly evaporated when Arius’ views were explained more fully, however. Eusebius of Nicomedia was first to speak. As he proceeded to explain the Arian position to the bishops, they became so angry that they grabbed his notes out of his hands and proceeded to tear them to pieces. On the face of it, this may seem to be a rather extreme, if not comical, reaction. But one must bear in mind that there were many bishops who still bore the scars of persecution from earlier times when the church was less in favor, and therefore had good reason to see this as a personal affront. The fifth century historian, Theodoret, writes:

Paul, bishop of Neo-Caesarea, a fortress situated on the banks of the Euphrates, had suffered from the frantic rage of Licinius. He had been deprived of the use of both hands by the application of a red-hot iron, by which the nerves which give motion to the muscles had been contracted and rendered dead. Some had had the right eye dug out, others had lost the right arm. Among these was Paphnutius of Egypt. In short, the Council looked like an assembled army of martyrs. (43)

Link:
http://en.m.wikiversity.org/wiki/Council_of_Nicea_(325_A.D.)

GILL COMMENTARY:
“Is it not lawful for me to do what I will with mine own?…. External gifts and outward privileges, such as enjoying the word and ordinances, are God’s own; and he may, as he does, bestow them on whom he will, and when and where he pleases; as he gave them to the Jews, and continued them many hundred years, when the Gentiles were utterly with them destitute of them; and as he has bestowed them in a more abundant manner for a long time on the Gentiles, whilst the Jews despise and reject them. Special grace is his own, which he gives to whom he pleases; it is by his own grace, and not the merits of men, that any are chosen, adopted, justified, pardoned, regenerated, and called; that they have faith, hope, love, repentance, or perform new obedience from a new heart, and new principles. Heaven and glory is his own, of his own preparing and giving; and both grace and glory are disposed of, and that very rightly and lawfully, according to his sovereign good will and pleasure: he chooses, adopts, justifies, pardons, regenerates, calls, and sanctifies whom he pleases; and brings what sons to glory he thinks fit, and bestows it equally upon them: and in so doing, does no wrong, or any injustice to any of his creatures; not to the fallen angels, by choosing some of their species, and confirming them in their original constitution; and by leaving them, the fallen angels, in their apostasy; nor by making provision for fallen man, and not them, nor by punishing them with everlasting destruction; nor do they ever complain of any wrong being done them: nor to non-elect men; for none of Adam’s race have any right to grace or glory, and therefore no wrong is done to any of them, by withholding them from them, whereby nothing is taken from them, and given to others; and by punishing them for sin; nor to any elect men, by making others partners with them; since they are all alike by nature, unworthy of grace and glory, and deserving of wrath: what is enjoyed by any of them, is of mere grace, and not through merit; and one has not a whit the less, for what the other is possessed of; so that there is no room for envy, murmuring, and complaint:”