His incarnation can be felt in humans

Sri Ramakrishna would explain to his devotees the mystery of incarnation in the following way “However great and infinite God may be, His Essence can and does manifest itself through man by His mere will. God’s Incarnation as a man cannot be explained by analogy. One must feel it for oneself and realize it by direct perception. An analogy can give us only a little glimpse. By touching the horns, legs, or tail of a cow, we in fact touch the cow herself; but for us the essential thing about a cow is her milk, which comes through the udder. The Divine Incarnation is like the udder. God incarnates Himself as man from time to time in order to teach people devotion and divine love.” 

But some devotees like Narendra would argue, “Is it ever possible to know all of God?  He is infinite.”  In reply Sri Ramakrishna would say that, “Who can comprehend everything about God? It is not given to man to know any aspect of God, great or small. And what need is there to know everything about God? It is enough if we only realize Him. And we see God Himself if we but see His Incarnation. Suppose a person goes to the Ganges and touches its water. He will then say, ‘Yes, I have seen and touched the Ganges.’ To say this it is not necessary for him to touch the whole length of the river from Hardwar to Gangasagar.” 

Further, Sri Ramakrishna would say that if a person touches the feet of another it is same as touching the very person.  Similarly, if a person goes to the ocean and touches the water, that person has certainly touched the ocean itself. 

Again, fire, as an element, is present everywhere, but in wood it is present to a great degree.  Thus Sri Ramakrishna would say that although God is omniscient His manifestation is specially felt in certain human beings in whom extraordinary divine qualities are clearly perceptible.