"This one thing I do" (Phil. iii. 13).
One of Satan's favorite employees is the switchman. He likes nothing better than to side-track one of God's express trains, sent on some blessed mission and filled with the fire of a holy purpose.
Something will come up in the pathway of the earnest soul, to attract its attention and occupy its strength and thought. Sometimes it is a little irritation and provocation. Sometimes it is some petty grievance we stop to pursue or adjust. Sometimes it is somebody else's business in which we become interested, and which we feel bound to rectify, and before we know, we are absorbed in a lot of distracting cares and interests that quite turn us aside from the great purpose of our life.
Perhaps we do not do much harm, but we have missed our connection. We have got off the main line.
Let all these things alone. Let grievances come and go, but press forward steadily and irresistibly, crying, as you haste to the goal, "This one thing I do."