Wonder: A feeling of surprise mingled with admiration, caused by something beautiful, unexpected, unfamiliar, or inexplicable.
He is the sign. He is the wonder.
These lyrics point to something inexplainably amazing about God. He is the wonder. Notice it says "the" not "a" because He is the beauty above all beauties, and the perfection of all that we see and do not see. The more we know Him, the more we find this to be true. A boring God is no God at all.
His wisdom is infinite. His compassion is overwhelming. A greater love we could not find, for infinitude is above all things. The nature of our spirit is to desire His spirit, and we were indefinitely created to love and be loved. That is what it's all about; loving God due to the love He has shown us, then out of that love we desire to bring others to Him.
My end point is this. If God is boring to you, you must be worshipping the wrong God (or have the wrong definition of the right God). His very nature is to astound us and conform us to it. To motivate us to new revelations while still satisfying. This is an absolute truth.
The more I seek Him, the more I find Him
The more I find Him, the more I love Him.