The Dao was an ephemeral existence, it was a concept as much as it was an object. It makes sense yet it doesn't. In layman terms you could just as well say that the Dao was the spark that truly gave life and purpose to all cultivators. A spark… and a key, in fact in all honesty Divyat had pondered on the existence of the Dao long before he ever got a chance to cultivate.
And what he has understood from it was that the Dao was unique in perception to each person. Just as he had an idea of what it was, Kane would probably had a different meaning to it too. For Divyat the Dao was a spark and a key, or rather the spark itself was the key. The key that would open the door to not just the secrets of the universe, but the building blocks of reality and existence itself.