Are spiritual people those who believe in God? What about agnostics who seem to be living more or less ideal lives? Without professing any devotion to God , they are a beacon light to their society. Surely, it is better to live an ideal life pleasing to god than mutter the name of the Lord and don't walk according to his will.
For example satya sai baba was not god but he did things which pleased god which in turn made people to believe in him and live a holy life!So how about we say then that spirituality is about getting better. It is the strife to improve oneself in gods will.(what is gods will? answer in bible)..If a man be very good, but does not get better, he stagnates spiritually.
Thus, spiritual people are those who walk for and do things what god has done,but are not god.
It is the state of a Buddha , Christ , Mohammed and all those revered personalities who followed their master.
God is only one we just need to follow him to be his child! or to be the so called spiritual !