The earliest appearance of Tarot cards was an an educational tool, as is evidenced by the symbology deployed. Then can also be used as a means of assessment, and the origins of 'tarot reading' goes back to this master-student relationship.
Today however, almost exclusively from the 18th century on, tarot cards have been presented and used as a means of divination or foretelling the future, either individual or general. Decks are sold exclusively for this purpose, and a small industry of 'explaining' the cards has grown up around it. In that sense reading the tarot is no different to reading palms, crystal balls, tea-leaves, runes, entrails, clouds, etc. — all are means of occupying the mind to allow the wider senses to roam free.
These 'wider senses' need not be considered psychic or esoteric or magic ... in the same way that Harry Houdini went round debunking and revealing the hidden table-rapping tricks of false spiritists, psychologists and especially practitioners of NLP like Darren Brown have clearly shown how a 'medium' can manipulate an audience, even perhaps unconsciously and convinced of their own abilities, and further that the audience, especially in a one-on-one situation like a reading, conveys and transmits all manner of subtle signals that the attuned reader (again unconsciously) will read and respond to.
(The story of mediums bringing messages from the dead always seem to be claming and concilliatory. I have yet to hear of someone coming back to criticise a living relative!)
The Catechism of the Catholic Church offers an overview in discussing practicies of divination which some sentimental souls might find offensive, but it's nonetheless true: "Consulting horoscopes, astrology, palm reading, interpretation of omens and lots, the phenomena of clairvoyance, and recourse to mediums all conceal a desire for power over time, history, and, in the last analysis, other human beings..."
To seek guidance from any other source than Christ is thereby a denial of Christ ... it's a fine line ...
Having said that, have you come across "Meditations on the Tarot: A Journey into Christian Hermeticism"?
The 'anonymous author' was a student of, and set to be the successor to, Rudolf Steiner's School of Anthroposophy, but underwent an epiphanic experience whilst contemplating the stained glass windows at Chatres Cathedral, and converted to Roman Catholicism. His "Meditations" is his magnum opus, and utilises the major arcana as a means of discussing Christian Hermeticism and an authentic 'Christian esoterism' (as opposed to the ersatz 'esoteric Christianity').
The "Meditations" declares: "The book is written from an orthodox Christian (Roman Catholic) perspective. One of its beauties is the way it draws out the value in many spiritual and cultural phenomena of which Christians have often been wary, without in any way compromising the centrality of the life, death and resurrection of Jesus Christ. The author uses the Tarot images to help the reader deepen his or her relationship with God through prayer and meditation."
The book has been seen in the possession of many popes, JP-II, Benedict XVI and Francis. A foreword was written by Hans Urs von Balthasar (one of the foremost theolgians of the last century):
"A thinking, praying Christian of unmistakable purity reveals to us the symbols of Christian Hermeticism in its various levels of mysticism, gnosis and magic, taking in also the Cabbala and certain elements of astrology and alchemy. These symbols are summarised in the twenty-two so-called "Major Arcana" of the Tarot cards. By way of the Major Arcana the author seeks to lead meditatively into the deeper, all-embracing wisdom of the Catholic Mystery... "
"The first discussions for or against the secret teachings of the Cabbala go back to the converted or non-converted Spanish Jews of the twelfth century. Among those who later endeavored to understand these teachings were Reuchlin in Germany, Ficino and especially Pico della Mirandola in Italy, whilst the extraordinary Cardinal Giles of Viterbo (1469-1552) wanted to explain the Holy Scripture with the help of the Cabbala "with a method that is not foreign, but which is intrinsic (to it)". Enjoined by Pope Clement VII, this zealous, reform-hungry Cardinal wrote his ebullient dissertation on the "Shekinah", dedicated to Emperor Charles V. Alongside these few names resounding from the past, a multitude of lesser predecessors and imitators could be mentioned."
"Here the important point is that although this penetration into the secret teachings of pagan and Jewish origin was pursued in the spirit of humanism, in the hope of bringing new life into rigidified Christian theology through collecting such scattered revelation and illumination, no one for a moment doubted that despite the disparities everything could be accommodated into the true Christian faith. That Pico, in particular, did not aim at syncretism, he himself made quite clear: 'I bear on my brow the name Jesus Christ and would die gladly for the faith in him. I am neither a magician nor a Jew, nor an Ishmaelite nor a heretic. It is Jesus whom I worship and his cross I bear upon my body.' The author of these Meditations' could also have affirmed this oath of allegiance."
The point here is that the Meditations use the Tarot as an aid to deepening one's faith, not as a means of determining tomorrow ...
My own view echoes a quote above. Contemporary Christian authorities tend to a knee-jerk reaction when they hear such terms as 'Hermeticism', 'Gnosis', 'Cabbala', etc., the term too often fixed within the context of an historical conflict, rather than properly understanding the term in its universal aspect.
The 'Gnostics' of the early Christian centuries, for example, were poor theologians and equally poor philosophers – the Greek schools were particularly scathing – and their metaphysics was, it has to be said, most often risible.)
I regard the tarot, used properly, as one of those 'beauties ... of which Christians have often been wary'. But, it has to be acknowledged, in certain times and places, that suspicion was not without good reason.