I think the essentials of Christian faith can be usefully grouped into six areas:
1) Creator: We believe in God, the creator of heaven and earth. Not a being among beings, albeit exalted above others; rather, the source of all being, Being itself, ‘I am who I am’. One can take the word ‘God’ as defined by this; however, note that in some sense neither Buddhists nor Mormons profess belief in ‘God’ according to this definition.
2) Fall: We believe that human nature, at its core, longs for communion with God from which it has fallen due to willful disobedience. We are basically ‘bent’ and all our works and thoughts have fundamental distortion. In Henry James’ extended metaphor, humanity is a golden bowl but flawed.