“The most eminent saints, in Old and New Testament times, applied themselves to private prayer. “And Abram planted a grove in Beersheba, and called there on the name of the LORD, the everlasting God” (Gen. 21:33). Why did Abram plant that grove, but that he could have a secluded spot where he might pour out his soul before his Maker. “And Isaac went out to meditate in the field at the eventide” (Gen. 24:63): the Hebrew word for “meditate” also signifies to pray, and is elsewhere rendered “commune” and “pray.” So, too, Jacob, Moses, Samuel, David, Elijah, Hezekiah, etc., were men whose private devotions are recorded in Holy Writ.
Concerning Daniel, we read, “he kneeled upon his knees three times a day, and prayed, and gave thanks before his God” (6:10)—busy as he must have been, he allowed not public duties to crowd out private devotions.” AW Pink