How do you know you are perceiving the same God? Is there a unique concept of God (within Christianity)?
If so, since different people probably have their own interpretation on Bible/Christianity/God (albeit the differences between different interpretations could be subtle), how can you (i.e. the Christian community) know that the God you have in mind are the same?
I'm sure you're familiar of the story of the three blind men and the elephant. One of them finds the tail and concludes the elephant is soft, long and round. One of them finds the tusk and concludes the elephant is hard. One finds the side and concludes the elephant is like a wall.

They are all describing the same elephant, but they have caught on to different aspects of it. There is truth in each description of the elephant, but there is error if they assume their description is complete.

So the trick is not to assume your understanding is complete, and this explains the disagreements over the details. But you are all "pointing to" the same thing.