(10.) You will find it an interesting and profitable employment occasionally to read a given book through, for the purpose of seeing what light it throws upon some particular subject,--some point of Christian doctrine, duty, practice, character, &c. For example, go through with Acts, with your eye upon the doctrine of Christ's divinity. Then go through with it a second time, to see what light it throws on the subject of Revivals. Pursue the same course with other books, and in respect to other subjects. In this way you will sometimes be surprised to find how much you have overlooked in your previous reading. It will be perceived that I have laid out a very extensive and laborious work. But this is the great business of our lives; and, indeed, the contemplation of the glorious truths revealed in the Bible will form the business of eternity; and even that will be too short to learn the length and breadth, and height and depth, of the ways of the Almighty. Your affectionate Brother. LETTER V. _Prayer and Fasting._ "In everything, by prayer and supplication, with thanksgiving, let your requests be made known unto God."--PHIL. 4:6. MY DEAR SISTER, The subject of this letter is one of vital interest to every Christian. It is, therefore, of the utmost consequence, that it be both well understood and diligently practised. It seems hardly necessary to urge prayer upon the Christian _as a duty_. Every true Christian must feel it to be a soul-exalting _privilege_. It is his breath; without it, he can no more maintain his spiritual life, than animal life can be sustained without breathing. Prayer is an intimate communion with God, by which we unbosom our hearts to him, and receive communications of his grace, and fresh tokens of his love. What Christian, then, whose soul burns with divine love, will be disposed to apply to this holy employment the cold appellation of _duty_? Yet, God sees so much the importance of prayer, that he has not only _permitted_, but _commanded_ us to pray. Our Lord frequently directed his disciples, and us through them, to "watch and pray." He also teaches us to persevere in prayer: "Men ought always to pray, and not to faint." The apostle Paul is frequent in exhorting Christians to pray: "Pray without ceasing." "I will that men pray everywhere." "Praying always, with all prayer and supplication in the Spirit." "I exhort, therefore, that, first of all, supplications, prayers, intercessions, and giving of thanks, be made for all men." "Continuing instant in prayer." The duty of prayer is also enforced by the example of all the holy men whose biography is given in Scripture. Moses, Samuel, David, Elijah, and all the prophets, were mighty in prayer. So were also the apostles. But, above all, the Lord Jesus, our blessed pattern, has set before us a life of prayer. You will find it very profitable to read the lives of these holy men, but especially that