8 Then, in the case of the publican, who excelled the Pharisee in prayer, [we find] that it was not because he worshipped another Father that he received testimony from the Lord that he was justified rather [than the other]; but because with great humility, apart from all boasting and pride, he made confession to the same God. The parable of the two sons also: those who are sent into the vineyard, of whom one indeed opposed his father, but afterwards repented, when repentance profited him nothing; the other, however, promised to go, at once assuring his father, but he did not go (for “every man is a liar;” “to will is present with him, but he finds not means to perform”)—[this parable, I say], points out one and the same Father.
Then, again, this truth was clearly shown forth by the parable of the fig-tree, of which the Lord says, “Behold, now these three years I come seeking fruit on this fig-tree, but I find none” (pointing onwards, by the prophets, to His advent, by whom He came from time to time, seeking the fruit of righteousness from them, which he did not find), and also by the circumstance that, for the reason already mentioned, the fig-tree should be hewn down. And, without using a parable, the Lord said to Jerusalem, “O Jerusalem, Jerusalem, you that kill the prophets, and stone those that are sent unto you; how often would I have gathered your children together, as a hen gathers her chickens under her wings, and you would not!
Behold, your house shall be left unto you desolate.” For that which had been said in the parable, “Behold, for three years I come seeking fruit,” and in clear terms, again, [where He says], “How often would I have gathered your children together,” shall be [found] a falsehood, if we do not understand His advent, which is [announced] by the prophets— if, in fact, He came to them but once, and then for the first time. But since He who chose the patriarchs and those [who lived under the first covenant], is the same Word of God who did both visit them through the prophetic Spirit, and us also who have been called together from all quarters by His advent; in addition to what has been already said, He truly declared, “Many shall come from the east and from the west, and shall recline with Abraham, and Isaac, and Jacob, in the kingdom of heaven.
But the children of the kingdom shall go into outer darkness; there shall be weeping and gnashing of teeth.” If, then, those who do believe in Him through the preaching of His apostles throughout the east and west shall recline with Abraham, Isaac, and Jacob, in the kingdom of heaven, partaking with them of the [heavenly] banquet, one and the same God is set forth as He who did indeed choose the patriarchs, visited also the people, and called the Gentiles.
Source: Adversus haereses (New Advent)