Below are selections from the series of hymns by St. Romanos the Melodist titled On the Mission of the Apostles.
The Leader gathered together the lambs whom fear had scattered at the time of the crucifixion after the resurrection, and standing on the mountain top, He sang a sweet song, giving courage to the flock, a bit as though speaking with hints for timid men, He said: "Be of good courage, I alone have conquered the world, I alone have scattered the wolves, no one was with Me; I was the one, the only one, Who alone knows what is in the heart."
I send forth one word for all so that I may not weary you in teaching you one by one. Once and for all I say to My saints: Go forth into all the world; teach races and kingdoms; for all things have been given Me by My Father, things on earth and in heaven over which I was in charge before I assumed flesh. And now I have become King of all, and I have you as my sacred senate. I Who alone know what is in the heart.
"Save the world on these terms, baptizing them in the name of the Father, and the Son, and the Holy Spirit." Strengthened by these words, the Apostles said to the Creator: "Thou art God before all time and without end. We shall herald Thee as one Lord, along with the Father and the Holy Spirit, just as Thou hast commanded, O Thou Who alone knows what is in the heart."
O Peter, lovest thou Me? Feed My flock, and love those whom I love. Sympathize with sinners, and heed My mercy to thee, since I received thee who hadst thrice denied Me; I Who alone know what is in the heart.
Instead of Iscariot I provide you with the Cilician; instead of the treacherous one, the man of excellence; instead of the traitor, Paul. All men will cudgel him with insults, and throw him into prison; and binding him cruelly, they will give him over to the rulers; but I shall not leave him orphan, for I am with him even unto the end; I Who alone know what is in the heart.
Be strong in Me; and you, too, Andrew; just as you were the first to find Me, you were found by Me; so find the one who has wandered. Do not forget your first skill; from it I shall educate you for this new art. Formerly, naked into the deep sea, now naked into life; formerly, hunting with a fishing-rod, now taught to fish with the cross; formerly, you used a worm as bait; now I order you to hunt with My flesh. I Who alone know what is in the heart.
St. James, Son of Zebedee
So, too, James, do not neglect thy work as herald, and remember Zebedee for whom thou formerly labored; for thou knowest how thou didst send thy father away in a boat, and didst love Me, the Creator. Together with thy fellow servants, carry out My will. Do not fear treachery, for I have set at naught their plots. When they stab thee with swords, think how My side hath been pierced with a spear; I Who alone know what is in the heart.
O John, accept now thy work. Let all men learn that it was not in vain that I formerly had thee lean on My breast. Make furrows for My torrent, by whose water thy love hath been nourished. With thy tongue, as with a hoe, dig for Me a channel. Lo, I shall come when thou didst wish it, and offering drink, I shall irrigate thy seed. Cast thy words forth like kernels, and I shall increase and fill out thy harvest: I Who alone know what is in the heart.
Come thou with the others, O Philip; herald Me as thou now seest and hearest Me; do not separate Me from My Father. Say not: "I saw the Son, but I did not see His Father at all." For I showed thee Him in Me and Me in Him. I did not come apart from Him; what He willeth, I bring to pass; what I will, He bringeth to pass. We are in the same Spirit. I send thee forth as a herald of Him; I Who alone know what is in the heart.
Bartholomew, My friend, brother, initiate - for I call thee initiate, and no longer servant, but son and co-heir with Me - thou art a light of the universe and bright beam of My sun; faithful guardian of My treasures; pillar of My Church Who I brought up from the sea; I Who alone know what is in the heart.
O Thomas, through thy present faith, abandon thy former words of faithlessness and self-distrust, and herald the One Who thou dist touch. The time hath come to attack those who doubt. Thou hast clear evidence of the resurrection; though hast seen and probed the prints of the nails and the marks of the spear. Indeed, thou shalt participate in My sufferings, for thou shalt be pierced in five places like Myself, Who alone know what is in the heart.
O Matthew, remain thou as tax collector, and collect from the enemy of Adam as once thou collected from travelers. Do not stop until thou hast taken away from him every last penny. Sit down, guarding the road which leadeth to hades; and if thou findest the destroyer who doth traffic off My people, oppose him, and exact toll, and despoil him, as I tell thee; I Who alone know what is in the heart.
St. James, Son of Alphaeus
Go forth, O James, sowing the seed of repentance on the earth and watering it with doctrinal teachings. Show forth My grace to the world, for I am the Creator Who spake to the prophets: I Who alone know what is in the heart.
Go forth to all the world, and cast the seed of repentance in the ground, and water it with doctrinal teachings. See to it that no one who repenteth remaineth outside your net. For I rejoice in those who are converted, as thou knowest; I Who alone know what is in the heart.
At the wedding in Cana, I made water into wine at the behest of mine all-pure mother. There also, O Simon, I made your heart zealous to follow Me in faith; I Who alone know what is in the heart.
Great is the number of the virtuous! The list of all the apostles groweth long, for they have perfumed the earth. They are the branches of My vine, the field of the Cultivator on high. I have chosen thee, O Matthias, to fill the number of My twelve. Go forth and cultivate the earth with My teachings; I await the fruit of My vineyard; I Who alone know what is in the heart.
Be not troubled of heart, O Mark, neither let the enemy disturb thy spirit. Do not reason like a child, but become wise as a serpent; for on your behalf was I lifted up like the brazen serpent. Do not doubt thyself or abandon thy work as herald. I do not wish to conquer by force; for I have loved the foolish of the world; I Who alone know what is in the heart.
Athenians will be bested by Galileans; Nazareth will shake Corinth. Wherefore, herald Me, O Luke, to the world, as thou makest clear what I am. Henceforth hate parables and enigmas. Say that, being God and ineffable, I took on the form of a servant. Show how I voluntarily sustained wounds in the flesh. Being God, though immortal, I came to death in the body; and entombed as one condemned, I came forth from hades as Lord; I Who alone know what is in the heart.
St. James, Brother of the Lord
I will open wide thy mouth, O My brother, and fill it, that thou mayest be the first to do what thou preachest; for he who doth everything which he preacheth, is great. I alone know what is in the heart.