The Scripture tells us that no one has ever seen God, furthermore, we are also made aware that chosen people down the ages hear from God. We can also glean from the Scriptures that the degree or frequency or number of times that those chosen people hear from God and or the significance of their message, is a measurement of the amount of faith bestowed unto them by God. Hearing from God is a confirmation or verification of His existence. When God speaks, He makes sure that the recipient of His word knows that He, God is the One talking, by means of unique markers, or events or signs which could be prophetic in nature or definitely without natural explanation.
Romans 10:17; So, then faith comes by hearing, and hearing by the word of God.
John 1:1; In the beginning was the Word, and the Word was with God, and the Word was God.
John 10:27; My sheep listen to my voice; I know them, and they follow me.
Exodus 3:4; When the Lord saw that he had gone over to look, God called to him from within the bush, “Moses! Moses!” And Moses said, “Here I am.”
Acts 9:3-6; As he neared Damascus on his journey, suddenly a light from heaven flashed around him. He fell to the ground and heard a voice say to him, “Saul, Saul, why do you persecute me?” “Who are you, Lord?” Saul asked. “I am Jesus, whom you are persecuting,” he replied. “Now get up and go into the city, and you will be told what you must do.”
Hebrews 11:1; Now faith is confidence in what we hope for and assurance about what we do not see. 1 John 4:12; No one has ever seen God; but if we love one another, God lives in us, and his love is made complete in us.
Romans 12:3; For by the grace [of God] given to me I say to every one of you not to think more highly of himself [and of his importance and ability] than he ought to think; but to think so as to have sound judgment, as God has apportioned to each a degree of faith [and a purpose designed for service].
However, not everyone who witnesses acts of faith, or demonstrations of the existence of God, are recipients of the varying degrees of faith. This may have to do with the fact that with human beings; “Seeing is believing”, in addition to which most people are visually, set up. Not seeing God is a concept or state of being that is difficult or impossible to live with, which is why, many transfer their allegiance to a representative figure or persona. Whom in turn, becomes idols for them. Faith in God, therefore, puts man in a conundrum or catch 22; with the exception of the intended recipients of the assurances.
