When a believer says Jesus is God, what does it mean? Please do not repeat the scriptural evidence that proclaims it. If my salvation is dependent on believing it, I must know what it means. Who is the Jesus who is The God?
I think I want to add that for now, according to my own understanding, the man Yehoshua is god enough for me but I do not know how to understand he is The Father. How can I know he is the son and The Father? No scripture please.
From my perspective, Jesus Christ is God, but He is definitely not the same individual as His Father, who is also God. Are they they same God or two different Gods? Well, that all depends on what you understand the word "God" to mean. And does believing that they are two Gods constitute polytheism?
I see "God" as a title reserved for the three individuals who make up "the Godhead," as the word is used in the scriptures. Granted, there are a great many dictionaries to choose from, so my statement may not be 100% accurate, but I would say that most of the commonly used dictionaries will give the word "God" as a synonym for "Godhead." This would mean that, at least in certain situations, the words could be used interchangeably. When we use the word Godhead, we are using a word that is known to be a "collective noun" -- a noun that describes an entity composed of more than one individual. Other collectives nouns include "team," "corps," "congregation," and "family." When we use one of these words in a sentence, we use it with a singular verb. In other words, we say, "The family is coming to dinner," and "The team is playing very well." We know, however, by virtue of the fact that these words are collective nouns, that each one is made of several (or at least two) individuals. When we use the word "Godhead," we know the same thing to be true. We are speaking of an entity comprised of three members who are together referred to in the singular form. Since "God" and "Godhead" are synonyms, we can substitute the word "God" for "Godhead" and be referring to three individual beings at once.
So, Jesus Christ is not both the Son and the Father. People will tell you that one individual can be both a father and a son, and that's true. No father, however, can be his own son and no son can be his own father. This is the same whether we're talking about you and your father or Jesus Christ and His Father. They are two distinct individuals who, along with the Holy Ghost, are "one God" (or "one Godhead"). They are each fully divine, so they are each entitled to be called by the same title: God. But because they are absolutely and perfectly united in virtually every other aspect (will, purpose, mind, heart, power, glory, etc.), they are said to be "one." You don't have to believe that they are "one in substance" to accept the fact that Jesus Christ is God. The Bible never says they're "one in substance." It just says they're "one" and I just explained how that's possible.
Have you looked into the writings of the Fathers or the decrees of the Councils of Nicaea I and Constantinople I, or the intricacies of Trinitarian theology? If you had, then perhaps you would understand exactly the point I was trying to get across, and why the nitpicking with the terminology and the description matters.