As newborn babes, desire the sincere milk of the word, that ye may grow thereby: If so be ye have tasted that the Lord is gracious.
1 Peter 2:2-3 (KJV)
The Word of God is the spiritual food for our born again spirit. Just as we require physical food in order to be physically strengthened, so too our recreated spirit requires spiritual food in order to become strong within us. As we are fed and nourished by His Word daily, we taste of the joy and the fullness of life that is in Him.