Luke 13:20Meaning & Commentary from the Church Fathers

Just as a mustard seed, despite its diminutive size compared to other seeds, grows into a towering plant that provides shelter for many birds, the kingdom of heaven—represented by the new and sacred gospel of salvation—grows from humble beginnings to encompass all who seek refuge in it. These seekers are likened to sparrows, illustrating the contrast of human existence against the magnitude of God.

The Law given to the Israelites served to guide them, but since salvation under the mere semblance of the Law and its physical observations was insufficient, the need arose for the life-giving proclamation of the gospel, which has spread throughout the heavens. This necessity is hinted at in the Mosaic Law, which conveys a deeper mystery. It states, "And the Lord spake unto Moses, saying, Thou shalt make for thyself two trumpets of broken metal, of silver shalt thou make them, and they shall be for thee to call the assembly and to move the camp." Following this, it conveys, "And the priests, the sons of Aaron, shall blow the trumpets, and it shall be an everlasting law for your generations." This indicates both the preparatory role of the Law and the fulfillment reached through Christ, where the gospel offers a life and doctrine that transcends mere shadows and types. Thus, the Law functions as a trumpet, and it is also the joyous message of the gospel, which the prophet Isaiah references: “And it shall be in that day when the great trumpet shall sound.” Indeed, the great trumpet has been sounded through the voices of the holy apostles, reaffirming the first trumpet while also expanding its message; they consistently corroborate their teachings about Christ with the testimonies from the Law and the prophets.

The two trumpets of beaten silver symbolize that splendor—the glorious words of God, which are devoid of the world's darkness; the beating of the silver signifies the advancing and expanding nature of both the old and new gospels. At the resurrection of Christ, as the old Law was meant to lead to its spiritual understanding, we, who have received enlightenment in Christ, continue to proclaim the gospel's spread until it reaches all corners of the globe. The Law granted the priests the authority to sound the trumpets and direct the people; however, Christ bestowed upon His holy apostles the mission to preach His commandments. They reveal His mystery using these dual trumpets, declaring Him as “from the beginning being eyewitnesses and ministers of the Word,” and reinforcing their messages with true testimonies from the Law and the prophets. It is evident that the gospel, initially small, was destined to grow rapidly, as foretold by the prophet Isaiah, “that the whole earth was filled with the knowledge of the Lord, as deep waters cover the seas.” The proclamation of salvation flows abundantly like the sea, and its current cannot be resisted. The God of all creation has made this clear through the words of the prophet: “And judgment shall flow like waters, and righteousness like an impassable stream.” Here, He designates the gospel with the attributes of judgment and righteousness, assuring us that it will inundate the world like waters rushing in a powerful, unstoppable stream.

Conversely, one who, ensnared by thorns, leads a life of wickedness filled with corruption, who remains oblivious to his condition, plunging fearlessly and carelessly into the mire of indulgence and pursuing all fleshly desires without regard for his soul, surrendering entirely to a worldly mindset—if caught in such a state, he will be severed from life. No one will extend a helping hand to him, and his fate will be irrevocably sealed; neither wife, children, siblings, relatives, nor friends will offer any assistance, for God will abandon him entirely.

In the Gospel of Matthew, we discover that leaven was added to three measures of flour, aligning with our belief that the Son of God is concealed within the law, veiled by the prophets, and ultimately revealed through the preaching of the gospel, granting us a perfect faith sourced from these scriptures. Through the unification of all biblical texts, He expressed His essence within us, as we constitute His body, filling everything everywhere (Eph. 1:23). He was the Word of God, the mystery concealed for countless ages and generations (Col. 1:26) — an eternal being, though hidden from the wicked, revealed to the saints, and destined for glory from before time itself (1 Cor. 2:7; 1 Tim. 3:16). Therein lies our glory as brethren, as we explore the divine mystery that has been concealed for ages within God (Eph. 3:9). What exists in God must surely derive from God: it is impossible for Him to embody another essence.

Some interpret this parable regarding the transformation of the world through the leaven of the law, the prophets, and the gospel, so that every tongue will acknowledge the Lord (Phil. 2:11; Rom. 14:11). Thus, let us engage in earnest scrutiny, for one cannot uncover truth without diligent searching. Let us erect a tower and assess the cost of the Scriptures (Luke 14:28), ensuring that no one can say, ‘This man began to build and was unable to complete it’ (Luke 14:30). Anyone who seeks to construct must lay a solid foundation, which is faith — the very foundation established by the apostles and prophets (Eph. 2:20). Our faith arises from both Testaments, and one who claims equal measures of perfect faith in both will be correct, as the Lord Himself affirms, ‘If you believed Moses, you would also believe Me,’ (Jn. 5:46) because He spoke through Moses also. There is indeed a complete measure in both, since in both the Lord is whole, and faith remains consistent (Eph. 4:13), as there is one power and understanding in prophecy and fulfillment.

I choose to adhere to the words of the Lord: that leaven symbolizes the spiritual teaching of the Church. The caution regarding ‘the leaven of the Pharisees’ (Matt. 16:6; Mark 8:15), alongside the apostolic statement, ‘not with the leaven of malice and wickedness’ (1 Cor. 5:8), clarifies that leaven conveys teaching. However, the leaven differs for tares compared to wheat. Aligning with insightful interpreters, we assert that through spiritual leaven, the Church sanctifies the renewed person, who is made up of body, soul, and spirit. Both body and soul experience sanctification, and spiritual grace enhances sanctity when grace is disseminated, dissolved, and integrated throughout the entire being, resulting in unity through the Church's actions and scriptural teachings enriched by divine words. This unity is realized when the three components harmonize in a single aspiration, supported by a united will.

The Church’s work is deliberate and not arbitrary; it emerges after careful thought to ensure these three aspects are joined and liberated from the law of sin. The apostle asserts, ‘And may the God of peace Himself sanctify you completely, and may your spirit, soul, and body be preserved blameless at the coming of our Lord Jesus Christ’ (1 Thess. 5:23). Due to earthly trials, this sanctification is possible only when the evangelical woman incorporates three measures of flour, representative of the leaven likened to the kingdom of heaven, until the entire mixture rises. As previously mentioned, these three measures correspond to body, soul, and spirit. We truly thrive through the spirit while we inhabit our bodies, and we truly live by the spirit if we do not allow the desires of the flesh to dominate or let the soul succumb to physical sins, thereby maintaining the integrity of life within the entire person. Given the challenge of preserving harmony without the Church's guidance and her teachings, the woman, symbolizing the Church, enriches the three measures with the potency of spiritual doctrine until the entire innermost heart of humanity is transformed (1 Pet. 3:4) and elevated to the grace of heavenly sustenance. It is correct to identify the doctrine of Christ as leaven, because Christ Himself embodies the bread, as the apostle notes, ‘One bread, and we, though many, are one body’ (1 Cor. 10:17).

The leaven unifies when the flesh no longer resists the spirit, nor the spirit opposes the flesh (Gal. 5:17), allowing us to put to death our earthly deeds (Rom. 8:13). Then the soul, recognizing that it has drawn the breath of life from God’s Spirit (Gen. 2:7), will reject worldly concerns and the shackles of the present age. Thus, the Apostle instructs us to live not according to the flesh but in accordance with the spirit, so that, through the washing of regeneration (Titus 3:5), we may discard the old man with its desires and don the new man, made in the image of Christ (Col. 3:9; Rom. 7:6), and walk in spiritual renewal rather than in the obsolete letter. By this means, we can preserve the unity of body, soul, and spirit intact at the resurrection, and we are able to receive all that we request. Many believe this is what the Lord indicates by saying, ‘If two of you agree on earth, concerning anything that they ask, it will be done for them by My Father in heaven’ (Matt. 18:19).

Others interpret ‘two’ as representing the soul and body, while some perceive it as soul and spirit. For indeed, if, while here on earth — that is, within the body, soul, and spirit — they come into agreement and do not contend against one another with opposing desires, anything they request will be granted. This occurs when one is constructed from two; if they set aside enmity, the soul and spirit unite to form one new being, enabling us to pray with both spirit and intellect (1 Cor. 14:15). Although some interpret these two as referring to two distinct individuals, one from Israel and another from the Gentiles, united at the resurrection for the fullness of perfection and the cessation of what is partial (1 Cor. 13:10), others suggest it pertains to a husband and wife in harmonious love.

If in this life the three measures maintain a united leaven until they rise and blend into one, obscuring the distinctions among their parts, then in the future, an eternal unity will emerge among those who love Christ, and we will no longer remain a collection of many. While we may currently exist as a gathered community, we shall be transformed into a singular entity (2 Cor. 3:18) and, at the resurrection, not one measure will fall short of another. Our fragile flesh presently experiences decay, and under ordinary conditions, the body remains susceptible to wounds and ailments, unable to transcend earthly limits or ascend to the heavens. Yet, we shall be wonderfully transformed into a radiant and unified being when John's proclamation comes to fruition: ‘Beloved, we are now children of God, and it has not yet been revealed what we shall be. We know that when He is revealed, we shall be like Him’ (1 John 3:2). Just as God's nature is simple—‘for God is spirit’ (Jn. 4:24)—so too shall we be conformed to His image: as He who is in heaven, so shall we who abide in heaven. And as we have borne the earthly likeness, we shall likewise embody the image of the heavenly person (1 Cor. 15:48-49), which our spirit must be clothed in.

Observing the joy and fascination of the multitudes drawn to Him through His miraculous works, Jesus recognized the initial stage and prophetic vision of His Church's eventual worldwide expansion, which at that time consisted of only a handful of followers, and He articulated a prophetic message concerning this growth.

In this very scenario, your strength will become evident, as you who are surrounded by the multitude will stand firm. Just as leaven affects the dough only when it is in genuine contact and mixes with it, so too will you prevail when you form a steadfast bond and unity with your adversaries' (St John Chrysostom. Interpretation on the Gospel of Matthew. 45).

Just as the mustard seed naturally develops into a great tree, and leaven inherently causes the dough to ferment, so too must the New Testament kingdom, despite its modest origins, extend its reach throughout the world, infusing it with its transformative essence. Its establishment would not demand violent revolutions or fierce conflicts, as many might have anticipated. Instead, the Saviour conveyed that the kingdom of heaven would emerge victorious through the inherent power of truth and, through that power—rooted in faith and love—it would renew the world.