"We cannot keep two things in mind at once. Indeed we cannot keep one thing in mind more than half a second. Our mind is a flowing something. It oscillates. Concentration is merely the continuous return to the same problem from a million angles. We do not think of one thing. We always think of the relationship of at least two things, and more often of three or more things simultaneously. So my problem is this: Can I bring the Lord back in my mind- flow every few seconds so that God shall always be in my mind?"
I choose to make the rest of my life an experiment in answering this question."
- Frank Laubach "Practicing His Presence"