Doctrine of Christianity

What is the central doctrine of Christianity for you?

Hmmm not quite sure what you mean by that..could it be the first principles (elementary principles) as found in Heb 6 : 1and 2

This foundation is so important to teach to every new believer Im surprised that many churches dont teach this "milk of the word" to every babe in Christ from the start.
As a non-denominational Christian Pastor and educator, that question is as simple for me to answer as reading and living John 3:16 (KJV).

16For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.

Once we accept and believe in our heart that Christ is our Savior, He becomes our Light, our Food, our Shelter, our Warmth, our Love, our Friend, our Father, our Church and our Teacher. Who could possibly need more than that?

Immediately I thought of these scriptures:

For by grace you have been saved through faith, and that not of yourselves, it is the gift of God.

Not of works, lest anyone should boast. Eph. 2:8-9

That's the doctrine of Christianity to me....

That's the 'whole' Gospel to me...
The New Testament tells us of one thing that would encompass everything:

For all the law is fulfilled in one word, even in this; Thou shalt love thy neighbour as thyself
Gal 4:14