The Bahá'í Religion could justifiably be called the "Religion of the Heart."
Statistically for example in the Gleanings from the Writings of Bahá'u'lláh the heart is the most frequently used word after God. God 995, Heart 236, Revelation 229, Divine 142 and all other words, like Love, Faith, Hope, Justice, Unity (together with Oneness) Knowledge, Mankind are used less than 100 times.
The heart in the Bahá'í Writings is given a special meaning; concepts like the city of the heart and the citadel of the heart are emphasizing the importance of the heart. The heart is described as possessing sensory capacities. Bahá'u'lláh talks about the "eye of thine heart" (KI 90),"ear of his inmost heart" (SLH 86),"hearts have been sorely shaken" (PM 12) and the "wise and understanding heart" (ESW 65) and suggests that one "Ponder this in thine heart" (ESW 74).
These statements can be correlated with the findings of modern Neurocardiology, which describes the "little brain" of the heart, having perception, memory and decision making ability.
Recent work in the relatively new field of Neurocardiology has firmly established that the heart is a sensory organ and a sophisticated information encoding and processing center. Its circuitry enables it to learn, remember, and make functional decisions independent of the cranial brain.
The question raised in this presentation is about the form and style of the language of the heart, in what way is this language different from our normal language and thinking as it is developed in the human brain. There are about 2,000 heart transplants made in the USA annually, giving us a stuffiest large number to study what is in the heart and how does the recipient of these transplants experience the new heart. There is evidence that dreams can be transplanted together with the heart from one person to another. The conclusion can be made that the language of the heart is similar than the language of dreams and that dreams can be stored in the heart.
Studying dream language, the following distinction needs to be made.
The logic that we miss in the dream work is the syntactical logic of speech - the syntactical logic that is essential for the framing and testing of propositions and reasoning from them. 
Consequently dreams express syntactical logic differently, for example causality is expressed in terms of contiguity, contradictions and conflicts are described by following pictures that are contradictory, as will be exemplified in the presentation.
Another conclusion is made by this author from seeing many patients with Post-traumatic Stress disorder that memories heavily loaded with emotions seem to be located in the heart and not in the brain, therefore they can be transplanted with the heart and are difficult to remove and will disturb the patient for a long time.
Other important conclusions are
There is no awareness in the heart like it is in the brain.
The heart's language becomes only aware in the brain (e.g., when dreams are remembered).
The logical brain cannot adequately translate the language of the heart.
The hearts decisions, when becoming aware, are always experienced with certitude.
Their heart can perceive and know events that are far away in space or are in the future (this has q been scientifically proven).
There is a connection between the hearts of people that are close, like siblings, friend, lovers and people who are physically close, even when they are physically separated.
This explains Mass-phenomena where people in a group can be influenced through their hearts.
The requirement of a pure heart to understand the Bahá'í Revelation indicates that only with a pure heart you understand the language of the heart.
It seems that in every thinking process where the brain is used the heart is participating as well, as on the other hand; the heart's understanding has to be logically reasonable as well to be true.
This sheds some light at some fundamental truth about the heart revealed in the Bahá'í Writing:
The Báb has stated (provisional translation by Nader Saiedi)
Such conclusive truth hath been revealed through the gaze of the heart, and not that of intellect.
For intellect conceives not save limited things.
Verily, bound by the realm of limitation, men are unable to gaze upon things simultaneously in their manifold aspects. This it is perplexing for them to comprehend that lofty station.
No one can recognize the truth of the Middle Way between the two extreme poles except after attaining unto the gate of the heart and beholding the realities of the worlds, visible and unseen.
This seeing the truth of the Middle Way is described by Bahá'u'lláh as different from the relative logical understanding as the way to understand spiritual truth, often described as understanding the Unity in Diversity of reality and spiritual truth.
These statements are made in the sphere of that which is relative, because of the limitations of men. Otherwise, those personages who in a single step have passed over the world of the relative and the limited, and dwelt on the fair plane of the Absolute, and pitched their tent in the worlds of authority and command -- have burned away these relativities with a single spark, and blotted out these words with a drop of dew. And they swim in the sea of the spirit, and soar in the holy air of light. Then what life have words, on such a plane, that "first" and "last" or other than these be seen or mentioned! In this realm, the first is the last itself, and the last is but the first. (SVFV 27-28)
When Bahá'u'lláh reveals that the heart is the seat of the Revelation we need to consider that it is the human heart where this happens and we need to understand the language of the heart to understand the Revelation, we have to learn to think from reading the Writings of the Revelation.
Unlock, O people, the gates of the hearts of men with the keys of the remembrance of Him Who is the Remembrance of God and the Source of wisdom amongst you. He hath chosen out of the whole world the hearts of His servants, and made them each a seat for the revelation of His glory. (GWB 296)
Concluding it needs to be said that the faculty of reason, which is an endowment of the spiritual soul, uses different bodily instruments. i.e., the brain and the heart. They always need to work together, but they have different languages, so that spiritual truth has to be reasonable even in the logical linguistic sense, and the heart has to be pure in a moral sense, otherwise it will contaminate logical reason or even pervert it. Clearly we need both, a pure heart and clear mind to understand the Revelation of Bahá'u'lláh.
Rollin McCray, Ph.D. and Doc Childre, The Appreciative Heart, The Psychophysiology of Positive Emotions and Optimal Functioning, Published by the Institute of HeartMath, 14700 West Park Ave., Boulder Creek, California 95006, www.heartmath.org.
Michael Robins, "Another Look at Dreaming: Disentangling Freud's Primary and Secondary Process Theories," in Journal of American Psychoanalytic Association, 2004, 52, pp.361-362