Being a Tractarian, ressourcement, patristically-minded, first millennial, conciliarist, philorthodox kind of Anglo-Catholic, I have always inclined toward the Eastern teaching on doxological matters, and this includes an appreciation for the Eastern Orthodox view on the counter-reformation devotion to the Sacred Heart of Our Lord. Anglo-Papalists included this feast in the Anglican and English Missals, but the Sacred Heart tradition is relatively modern and certainly post-Tridentine, originating as it does in the seventeenth and eighteenth century 'southern catholicism' of the mediterranean countries. As such, it is not part of the devotional tradition of the ancient and patristic catholicism of the undivided Church, and hence does not play a part in my own understanding of orthodox theology or in my own devotional experience.
In this respect the Sacred Heart devotion is different from, say, the Holy Rosary of the Blessed Virgin Mary, a perfectly Western devotion, which I love and to which I am greatly devoted, and which is also part of the Orthodox tradition and that of the Great Church before 1054 - it was prayed continually by the eighteenth-century Russian Saint Seraphim of Sarov and is called 'the Rule of Prayer of the Mother of God' in the Eastern Churches. The Rosary of Our Blessed Lady is still very much part of the devotional lives of Christians Eastern Rite and Western Rite alike and has been used by both in one form or another since the eighth century. The Anglican devotion to Our Lady of Walsingham is likewise shared by East and West, as is, of course, the universal veneration of Holy Mary as the Spotless Ever-Virgin Mother of God. One of the strongest bonds between East and West is our common veneration of our common Mother.
Another example of common doxological practice shared by the Eastern and Western Rites, although expressed in different ways, is that of the adoration of Our Lord Jesus Christ in His true Body and Blood under the sacred species of the Eucharist. Although the East has no Corpus Christi devotion and no tradition of extraliturgical devotion to the Blessed Sacrament, it shares with the Western Rite the practice of adoring Our Lord in the Blessed Sacrament within the context of the Liturgy. All orthodox Catholic Christians, East and West, believe in the Real Substantial Presence of the Body and Blood of Christ and adore Our Lord objectively present in the Sacrament of the Altar. This tradition is Apostolic and is found in all of the most ancient Liturgies of the Church.
The Orthodox tradition speaks very clearly to the Sacred Heart devotion and maintains that it is not Christologically sound. With this judgement I am inclined to agree. The position of the Eastern Churches is quite compelling.
The following explanation is provided by a monk of the Eastern Church:
It would be difficult to accuse Roman Catholicism of denying the divinity of Christ, rather they have split the wholeness of Christ, emphasizing His human nature as a separate devotion, sometimes in a crudely biological way. This violates a central principle of the Councils, that devotion should be given to the devotion of Christ, and not to one of His natures, or parts of His body. Thus, by fragmenting the wholeness of the Son of God, a tendency develops to Nestorianize. Parts of the body of Christ should not become parts of isolated objects of adoration, nor should they be pictorially depicted (i.e., a heart on fire, or a heart crowned with thorns surrounding it).
A hieromonk of the Russian Church expresses a similar view:
The form taken by the newly forged devotion to Jesus' humanity as popularised by the Jesuits also strayed outside the bounds of Orthodox doctrine. We know that there have been seven Oecumenical Councils of the Church, from whose dogmatic teaching there can be no appeal. The Council of Ephesus (A.D. 431), responding to the teachings of Nestorius, the heretic Patriarch of Constantinople, taught that the Word, the second Person of the Trinity, was made man -- that He took a human body and a human soul -- that He appeared in the world under the name 'Jesus,' and under the title 'Christ.' Thus there is only one Person of Jesus Christ, and this Person is to be worshipped with a single worship, that of latria, the kind of worship rendered to God almighty. Nestorius, however, attempted to separate the honour paid to Christ's humanity from that offered His Divinity.
St. Athanasius of Alexandria pointed out the wrongness of worshipping Christ's body in a separate way, in these words: 'We do not worship a created thing, but the Master of created things, the Word of God made flesh. Although the flesh itself, considered separately, is a part of created things, yet it has become the body of God. We do not worship this body after having separated it from the Word. Likewise, we do not separate the Word from the body when we wish to worship Him. But knowing that 'the Word was made flesh,' we recognise the Word existing in the flesh as God.' (Ep. ad Adelph., par. 3)
The majority of Roman Catholic bishops issued pastoral letters to establish worship of the Sacred Heart, naming the physical heart as the object of worship. Offices were composed and inserted into the Missals and Breviaries, and prayerbook devotions abounded. Apologists for the devotion tried to exonerate it from charges of Nestorianism. (Nestorius honored Jesus as man in one way and Jesus as God in another; the Faith teaches us that we must worship Jesus Christ as one Person both human and Divine, not as one or the other separately.)
The apologists argued they worshipped the Heart for the sake of its union with the Godhead. What they forgot is that Nestorius himself, when cornered at the Council of Ephesus, also claimed he 'adored what was visible for the sake of that which was hidden.'
The historian Father Rene Francois Guettee remarks that by singling out for worship not only Christ's human body as opposed to His whole Person, but the heart as opposed to the rest of His body, an error even worse than that of Nestorius has been devised.
And finally this respectful and succinct explanation by Father Michael Pomazansky sums up the Eastern Orthodox tradition on the subject:
To the Lord Jesus Christ as to one person, as the God-man it is fitting to give a single inseparable worship, both according to Divinity and according to Humanity, precisely because both natures are inseparably united in Him. The decree of the Fathers of the Fifth Ecumenical Council (the Ninth Canon against Heretics) reads: 'If anyone shall take the expression, Christ ought to be worshipped in His two natures, in the sense that he wishes to introduce thus two adorations, the one in special relation to God the Word and the other as pertaining to the Man . . . and does not venerate, by one adoration, God the Word made man, together with His flesh, as the Holy Church has from the beginning: let him be anathema.'
In connection with this decree of the Council it may be seen how out of harmony with the spirit and practice of the Church is the cult of the 'sacred heart of Jesus' which has been introduced into the Roman Catholic Church. Although the above-cited decree of the Fifth Ecumenical Council touches only on the separate worship of the Divinity and the Humanity of the Saviour, it still indirectly tells us that in general the veneration and worship of Christ should be directed to Him as a whole and not to parts of His Being; it must be one. Even if by 'heart' we should understand the Saviour's love itself, still neither in the Old Testament nor in the New was there ever a custom to worship separately the love of God, or His wisdom, His creative or providential power, or His sanctity. All the more must one say this concerning the parts of His bodily nature. There is something unnatural in the separation of the heart from the general bodily nature of the Lord for the purpose of prayer, contrition and worship before Him. Even in the ordinary relationships of life, no matter how much a man might be attached to another — for example, a mother to a child — he would never refer his attachment to the heart of the beloved person, but will refer it to the given person as a whole.