The thoughts will be roving and dancing up and down in prayer, just as if a man who is travelling to a certain place should run out of the road, and wander he knows not whither. This is rather wandering than praying. The thoughts of this would make us hoc agere, mind the duty we are about. Set yourselves, when you pray, as in God's presence. Could you but look through the keyhole of heaven, and see how devout and intent the angels are in their worshipping God, surely you would be ready to blush at your vain thoughts and vile impertinences in prayer.
Much vanity comes in at the eye.
When the eye wanders in prayer, the heart wanders. To think to keep the heart fixed in prayer, and yet let the eye gaze, is as if one should think to keep his house safe, and yet let the windows be open. Love is a great fixer of the thoughts. He who is in love cannot keep his thoughts off the object. He who loves the world has his thoughts upon the world.