It is what it IS
The “Fihi Ma Fihi” is a prose work of Rumi written in Farsi (Persian). It consists of 72 discourses. Like Masnavi it was written during the last few years of Rumi’s life.
The literal translation of the term “Fihi Ma Fihi” is “In it what is in it”. I have also seen the translation of “There is in it what is in it”. Doug Marman pointed out that it should be translated as “It is what it is” which is closer to my interpretation of the inner meaning of “Fihi Ma Fihi”. In my opinion, we should pay attention to “is” in the sentence. I would write it as “It is what It IS”.
“Fihi Ma Fihi” refers to the “Immanent” aspect of the Cosmic Consciousness. Immanence, derived from the Latin in manere – “to remain within” – refers to the divine essence permeating the whole Cosmos and forming the basis of existence and life. Without this essence there is no existence and there is no life. The life giving essence is at the core of each entity from elementary particles to the entire Cosmos and from viruses to human beings. This essence is also known as the Soul. Unit Souls and the Cosmic Soul seem different but they are reflections of that nameless indescribable ocean of love and bliss. Rumi experiences this infinite ocean, he is unable to explain it and unable to describe it. He simply says “It is what It IS”.
The existential “I” or the soul which is also known as the “átman” was referred to as “I am that I am” consciousness in other philosophies. “It is what It IS” is another way referring to the existential “I” and sounds similar to the sentiment of “I am that I am”.
In modern times, there were similar expressions of this sentiment. In English language, no one expresses the “It is what It IS” sentiment better than P.F. Dziuban. He says 
“Consciousness IS” and he goes on to say that “There is nothing greater than consciousness.”, “Consciousness is what you are.”, “Consciousness is the infinite itself.”, “Consciousness is not the human mind.”, “The all-inclusiveness is consciousness.”, “Consciousness is neither physical nor metaphysical.”, “There is only one consciousness.”, “Consciousness is what the present is.”, “Love is what existence is.”, Consciousness cannot ignore its own presence.”, “The present is All that is present.”, “Time is not continuous.”, “The present is perfection itself.”, “Now is undelayable.”, “Ideas cannot withhold themselves.”
In the preface to A.J. Arberry’s translation of “Fihi Ma Fihi” Doug Marman says that:
” ‘It’ refers to God. Therefore God is what God is. This is the same as the Muslim saying, ‘There is no God but God.’ In other words, Rumi asks, ‘What more is there to say?’ All the words here, all the stories and explanations are saying nothing more than this. There is no more to reality than reality. God is. Reality is. It is what it is. Explanations cannot explain it. Words cannot reveal it.”
Subject and Supreme Subject
The Sanskrit term for the soul (unit consciousness) is átman. The term átman can be translated to English as “subject” or “witnessing entity”. But when we use the word “subject” or “witnessing entity” we lose the other meanings (“essence”, “life giving”, “sustainer”) of átman. Mind is different from átman. Mind which has five different layers conceals the átman. The átman is the subject (essence, life giver, witness) of the mind and the body.
There is the unit soul (átman) but there is also the Cosmic Soul (Paramátman). The relationship between the unit soul and the Cosmic Soul is a mystery. We can only defer to the sages to give us hints. Shrii Shrii Anandamurti reminds us that while átman is the subject of the mind and the body when it comes to the relationship of átman and the Paramátman, the átman is the object and Paramátman is the subject.
“Now regarding the relationship of átman and Paramátman, the átman is the object and the Paramátman is the subject. So Paramátman is the Supreme Subjectivity. He is the Supreme Subject of all other subjects. He is the supreme multiple of all other expressed multiplicities. Because He is the supreme – in Sanskrit “supreme” is parama – He is known as Paramátmá. He is the Supreme Subject.” 
In my “A Fundamental Principle” article I tried to explain the universal principle that “subjectivation is always followed by objectivation“. The “subject” is formed first. Subject is the cause of Object. Our átman is the first cause of our existence and life. Our life is the objectivation (expression, projection) of our soul with the help of the mind. The mind is projecting the potential contained in the “subject” (soul). The mind is externalizing what is internal. Earlier we said that the mind conceals the soul. Mind is concealing the soul while projecting it to the physical reality. This also means that the concealment of the soul is the necessary condition for the physical and mental existence. The concealment or constriction of consciousness creates life.
Similarly the Paramátman is the first cause of the Cosmos. In the article “A Fundamental Principle” I mentioned that the objectivation has to continue as long as the nucleus/center (soul, subject, átman) exists. Since the Cosmic Nucleus (Cosmic Soul) is the subjectivation of the infinite potential (Nirguna Brahma) the objectivation/creation will go on forever. The mind of Paramátman (Cosmic Mind) is projecting/externalizing the infinite potential of Nirguna Brahma as the Cosmos. The potential of Nirguna Brahma is infinite therefore the creation has to continue forever. The concealment or constriction of Cosmic Consciousness creates the Cosmic Life.
 Peter Francis Dziuban, “Consciousness Is All: Now Life Is Completely New”, Blue Dolphin Publishing, Inc (2006), ISBN 9781577331605
 Shrii Shrii Anandamurti, discourse “Fighting at each and every step” (date unknown)