"But the question may be asked: How shall we know God?"

"But the question may be asked: How shall we know God? We know Him by His attributes. We know Him by His signs. We know Him by His names. We know not what the reality of the sun is, but we know the sun by the ray, by the heat, by its efficacy and penetration. We recognize the sun by its bounty and effulgence, but as to what constitutes the reality of the solar energy, that is unknowable to us. The attributes characterizing the sun, however, are knowable. If we wish to come in touch with the reality of Divinity, we do so by recognizing its phenomena, its attributes and traces, which are widespread in the universe. All things in the world of phenomena are expressive of that one reality. Its lights are shining, its heat is manifest, its power is expressive, and its education, or training, resplendent everywhere. What proof could there be greater than that of its functioning or its attributes which are manifest?"
-'Abdu'l-Baha, Promulgation of Universal Peace, p. 422
10 November 1912