On Dogged Prayer
Dogged prayer reaches its goal. And if at the beginning prayer seems to you dry and stoney, still from this hardest of rocks you will squeeze the oil of grace if only you persevere, if protracted delay does not sap your strength, if your longings do not grow slack from deferral. Deferral is obviously painful to a lover but desires prolonged grow stronger.
Sermon 6.1; CF 14:98