The entire Fourth Book of The Imitation of Christ pertains to the Blessed Sacrament. It is, according to many Catholic spiritual commentators, the true gem and highlight of that entire work. The Imitation of Christ is the most loved and most read Catholic book of all time, second only to the Holy Bible.
There is a passage in Book IV of The Imitation that refers to the spirituality of self-oblation. Oblation means offering, but in the sense of a sacrificial offering. Thus self-oblation is the sacrificial offering of oneself to God. The supreme model and archetype of all self-sacrifice is, of course, Our Lord Himself on the Cross. Jesus Christ, on the Cross, is both Priest and Victim. He is both the One who is offering the Sacrifice and the Sacrifice itself that is offered.
Book IV, Chapter 9 of The Imitation of Christ invites the faithful disciple of Jesus to make of himself a self-oblation to God. Here is the relevant passage from Thomas a Kempis:
LORD, all things are Thine that are in Heaven and earth. I desire to offer myself up to Thee as a voluntary oblation, and to remain forever Thine. Lord, in the sincerity of my heart I offer myself to Thee this day to be Thy servant evermore, to serve Thee, and to become a sacrifice of perpetual praise to Thee. Receive me with this Sacred Oblation [Immaculate Victim OR Host] of Thy Precious Body, which I offer to Thee this day, in the presence of Thine angels invisibly standing by, that it may be for mine and all the people's salvation.
2. Lord, I offer to Thee all my sins and offences which I have committed in Thy sight and that of Thy holy angels, from the day that I was first capable of sin until this hour, upon Thy propitiatory Altar, that Thou mayest burn and consume them all with the fire of Thy charity, and remove all the stains of my sins, and cleanse my conscience from all offences, and restore to me Thy grace, which I have lost by sin, by fully pardoning me all, and mercifully receiving me to the kiss of peace. (Heb. 9:13, 14).
3. What can I do for my sins but humbly confess them, and lament them, and incessantly implore Thy mercy for them. Hear me, I beseech Thee, in Thy mercy, where I stand before Thee, O my God. All my sins displease me exceedingly, I will never commit them anymore; I am sorry for them, and will be sorry for them as long as I live; I am willing to do penance for them, and to make satisfaction to the utmost of my power. Forgive, O my God, forgive me my sins for Thy Holy Name's sake; save my soul, which Thou hast redeemed with Thy Precious Blood. (1 Ptr. 1:19). Behold, I commit myself to Thy mercy; I resign myself into Thine hands. Deal with me according to Thy goodness (Ps. 118:124), not according to my wickedness and iniquity. (Ps. 102:10).
4. I offer also to Thee all the good I have, though very little and imperfect; that Thou mayest make it better and sanctify it; that Thou mayest be pleased with it, and make it acceptable to Thee, and perfect it more and more; and mayest moreover bring me, who am a slothful and unprofitable wretch, to a good and happy end.
5. I offer to Thee also all the godly desires of Thy devout servants, the necessities of my parents, friends, brethren, sisters, and all of those that are dear to me; and of all such as, for the love of Thee, have been benefactors to me or others; or who have desired and begged of me to offer up prayers and Masses for themselves and all that belonged to them; whether they live as yet in the flesh, or whether they are now departed out of this world! That they all may be sensible of the assistance of Thy grace, of the benefit of Thy comfort, of Thy protection from dangers, and of a deliverance from their pains, and that being freed from all evils they may with joy give worthy thanks to Thee.
6. I offer up also to Thee my prayers and this Sacrifice of Propitiation [the Immaculate Host] for those in particular who have in anything wronged, grieved, or abused me, or have done me any damage or displeasure. And for all those likewise whom I have at any time grieved, troubled, injured, or scandalized, by word or deed, knowingly or unknowingly; that it may please Thee to forgive us all our sins and offences one against another. Take, O Lord, from our hearts all jealousy, indignation, wrath, and contention, and whatsoever may hurt charity, and lessen brotherly love. Have mercy, O Lord, have mercy on those that crave Thy mercy; give grace to them that stand in need thereof, and grant that we may be worthy to enjoy Thy grace, and that we may attain to life everlasting. Amen.
Notice that the language of oblation often contains the word "offer." Lord, I offer to Thee... The offering of oneself as a sacrifice to God, by uniting oneself to the Immaculate Host/Victim that is Jesus in the Most Blessed Sacrament, is a very pleasing thing to do in the eyes of God. It is, in fact, the only real gift that God wants from us, because it gives Him glory more than anything else. God the Father does not ultimately want anything material or physical from us — though it is good to offer to God our body as well as our soul. But the true sacrifice that the Father is asking us to give Him is the sacrifice of ourself, united to that of His Son. This is what St. Paul means in the Scriptures when he speaks of "living to Christ" and "dying to Christ." To live and to die to Christ (or for Christ) means to make one's entire life an offering or oblation to the Father through the Son and in the Holy Spirit: the Trinitarian offering par excellence.
When Jesus says in the Gospel, "Whoever wishes to be My disciple must deny himself, take up his cross, and follow Me (Mt XVI, 24)," He is inviting His true followers to imitate Him in their self-oblation and to make of their lives a continual sacrifice for the glory of His Father in Heaven.
The best way to make this sacrifice of self to God the Father is by uniting oneself to Jesus in the Most Blessed Sacrament, as The Imitation of Christ says. This is why the best time to make such an offering is at the very moment when the Priest at Holy Mass offers the bread at the Altar to God the Father: the very bread that will become the Sacred Body of Christ the Victim. The offering of the Immaculate Victim (Immaculate Host) takes place, in the traditional Mass, when the Priest raises the Host on the paten over the Altar and says in a quiet voice in Latin the Suscipe prayer:
Súscipe, Sancta Trínitas, hanc Oblatiónem, quam tibi offérimus ob memóriam Passiónis, Resurrectiónis, et Ascensiónis Jesu Christi, Dómini nostri: et in honórem beátæ Maríæ semper Vírginis, et beáti Joannis Baptistæ, et sanctórum Apostolórum Petri et Pauli, et istórum et ómnium Sanctórum: ut illis profíciat ad honórem, nobis autem ad salútem: et illi pro nobis intercédere dignéntur in cælis, quorum memóriam ágimus in terris. Per eúndem Christum, Dóminum nostrum. Amen.
The English translation is:
Receive, O Holy Trinity, this Oblation which we make to Thee, in memory of the Passion, Resurrection and Ascension of our Lord Jesus Christ, and in honour of Blessed Mary, ever Virgin, blessed John the Baptist, the holy Apostles Peter and Paul, and of all the Saints, that it may avail unto their honour and our salvation, and may they vouchsafe to intercede for us in Heaven, whose memory we celebrate on earth. Through the same Christ our Lord. Amen.
The Offertory is the most perfect moment when the faithful should offer to God not just their good works and merits, but also their shortcomings, failings, sacrifices, and their own crosses, uniting them to the One True Sacrifice that is about to be offered on the Altar by the hands of the Priest — the only Sacrifice that is in and of itself pleasing to God and that merits grace.
The Blessed Sacrament can therefore teach us how to unite ourselves to Christ the Son of God and live (and die) in Christ, thereby making of our entire lives a continual self-gift to the honour and glory of the Most Holy Trinity.