When meister Echhart said

The eye through which I see God is the same eye through which God sees me; my eye and God’s eye are one eye, one seeing, one knowing, one love.

What he meant can be understood through Bernardo Kastrup’s framework of Analytical Idealism:

Humans, in particular, seem to be unique in our ability to think symbolically, conceptually. Other higher animals—such as cetaceans, pachyderms, apes, and perhaps even some mollusks—also seem to have some degree of self-awareness. If the four-billion-year-long evolutionary drama is pushing towards something, it seems to be these high-level mental functions. Now notice that it is only through these high-level functions that nature can take explicit notice of itself; raise its head above the tsunami of instinctual unfolding and take account of what it is doing; perhaps even of what it is. It is only through life—through dissociation—that nature can ‘step out of itself,’ so to contemplate itself with some degree of objectivity. As Jung put it, this meta-cognitive scrutiny is a second act of Creation, for it bathes existence with the light of a new level of awareness. There is a sense, thus, in which we are ‘spies for God.’ We are in the unique position, after the unfathomable labor of four billion years of evolution, to contemplate nature from a vantage point not otherwise available to nature. Countless conscious beings have lived and died over countless eons, so we could stand here today, musing about the most profound questions of existence. And after a lifetime of insights in this regard, upon death—the end of the dissociation—we contribute those insights to the broader field of cognition that nature is.

Man’s ultimate concern must be expressed symbolically, because symbolic language alone is able to express the ultimate […]

Symbols have one characteristic in common with signs: they point beyond themselves to something else.

Decisive is the fact that signs do not participate in the reality of that to which they point, while symbols do. Therefore, signs can be replaced for reasons of expediency or convention, while symbols cannot.

This leads to the second characteristic of the symbol: It participates in that to which it points; the flag participates in the power and dignity of the nation for which it stands.

The third characteristic of a symbol is that it opens up new levels of reality which are otherwise closed to us. A picture and a poem reveal elements of reality which cannot be approached scientifically.

Symbols cannot be reproduced intentionally — this is the fifth characteristic. They grow out of the individual or collective unconscious and cannot function without being accepted by the unconscious dimension of our being.

The sixth and last characteristic of the symbol is a consequence of the fact that symbols cannot be invented. Like living beings, they grow and they die. They grow when the situation is ripe for them, and they die when the situation changes. […]

Is it not only in those cases in which the content of the ultimate concern is called “God” that we are in the realm of symbols? The answer is that everything which is a matter of unconditional concern is made into a god.

If the nation is someone’s ultimate concern, the name of the nation becomes a sacred name and the nation receives divine qualities which far surpass the reality of the being and functioning of the nation.

The reason for this transformation of concepts into symbols is the character of ultimacy and the nature of faith. That which is the true ultimate transcends the realm of finite reality infinitely. Therefore, no finite reality expresses it directly and properly. Religiously speaking, “God transcends his own name.”

Whatever we say about that which concerns us ultimately, whether or not we call it God, has a symbolic meaning. It points beyond itself while participating in that to which it points. In no other way can faith express itself adequately. The language of faith is the language of symbols. […]

Where there is ultimate concern, God can be identified in the name of God. One god can deny the other one. Ultimate concern cannot deny its own character as ultimate. Therefore, it affirms what is meant by the word “God.”

~ Paul Tillich, Dynamics of Faith, Chapter 3

The most ordinary misinterpretation of faith is to consider it an act of knowledge that has a low degree of evidence. […]

One believes one piece of information is correct. One believes that a scientific theory is adequate for the understanding of a series of facts. One believes that a person will act in a specific way.

The Christian may believe in the Bible writers, but not unconditionally. He does not have faith in them. He should not even have faith in the Bible. For faith is more than trust in an authority [or knowledge with a low degree of evidence]. It is participation in the subject of one’s ultimate concern with one’s whole being. […]

Faith does not affirm or deny what belongs to pre-scientific or scientific knowledge of our world, whether we know it through direct knowledge [sense perception] or through the experiences of others. […]

Almost all the struggles between faith and knowledge are rooted in the wrong understanding of faith as a type of knowledge which has a low degree of evidence. […]

The certitude of faith is “existential”, meaning that the whole existence of man is involved. It has two elements: a certainty about one’s own being, namely one’s being related to something ultimate or unconditional; the other, namely the surrender to a concern which is not really ultimate and may be destructive if taken as ultimate. […]

The difficulty of understanding faith as a matter of intellect has led to the interpretation of faith as emotion. This solution was supported by both the religious and the secular side. For religion it was a retreat to a seemingly safe position after the battle of faith as knowledge. For the other side, it was readily accepted because they took it as the best way to get rid of interference from religion in the process of scientific research. […]

Neither of the two sides, the religious and the cultural [secular], could keep this well-defined covenant of peace. […]

It [faith] does not accept the situation “in the corner” of mere feeling. If the whole person is grasped, all his functions are grasped. […] It was not only religion which could not accept the restriction of faith to feeling. It was also not accepted by those who wanted to push religion into the emotional corner. Scientists, artists, moralists show clearly that they also were ultimately concerned. […]

Certainly faith, as an act of the whole personality, has strong emotional elements within it. […] But emotion is not the source of faith. Faith is definite in its direction and concrete in its content. […] It is directed towards the unconditional and appears in a concrete reality that demands and justifies such commitments.

~ Paul Tillich, Dynamics of Faith, Chapter2

Faith is certain in so far as it is an experience of the holy. But faith is uncertain in so far as the infinite to which it is related is received by a finite being. This element of uncertainty [doubt] cannot be removed; it must be accepted. […]

[…] We must remember that faith as the state of ultimate concern includes total surrender to the content of this concern […]. This means that the existence of the personality in the ultimate sense is at stake. Idolatrous concern and devotion may destroy the center of personality. If, as in the Christian Church […], it is understandable that every deviation from the credence is considered destructive for the “soul” of the Christian. […]

All this drives to the question: How is a community of faith possible without suppression of man’s spiritual life?

No answer is possible if the character of the creed excludes the presence of doubt. [Without doubt] this faith has become static. […]

The fight against the idolatrous implication was waged first by Protestantism and then, when Protestantism itself became static, by Enlightenment. This protest, however insufficient its expression, aimed originally at dynamic faith and not at negation of faith, not even negation of creedal formulation. […]

So we stand again before the question: How can faith which has doubt as an element within itself be united with creedal statements of a community of faith?

The answer can only be that creedal expressions of the ultimate concern of the community must include their own criticism. It must become obvious in all of them—be they liturgical, doctrinal, or ethical expressions of faith—that they are not ultimate. Rather, their function is to point to the ultimate which is beyond all of them. This is what I call the “Protestant principle,” the critical element […] and consequently the element of doubt in the act of faith. […]

Certainly, the life of a community of faith is a continuous risk, if faith itself is understood as a risk. But this is the character of the dynamic of faith.

~ Paul Tillich, Dynamics of Faith, Chapter 1 §5-6