Try to turn your whole life into service to God; if you are reading anything at home, begin this work by a short fervent prayer that God may teach you and make you wise in faith and piety and in the careful accomplishment of your duties; never read idly, in order to pass the time; by thus doing you lower the word, which should serve entirely for our salvation, and not for idle words, nor as a means for pleasure and spending time agreeably. If you talk to your neighbor, speak reasonably, prudently, instructively, edifyingly; avoid idle speaking as the poison of a serpent, remembering that every idle word that men shall speak, they shall give account thereof in the day of judgment (Matt. 12:36)—-that is, they shall hear the just sentence of the Judge. If you are teaching children, your own or those of others, turn this work into God’s service, teaching them zealously, considering beforehand the best means of making the instruction clear, comprehensible, complete (as far as possible), and fruitful, Conquer by the name of the Lord and by the sign of the cross the snares of the enemy, who endeavors to disturb, darken, oppress, and weaken you. Even when you eat, drink, or do anything else lawful, do all to the glory of God (1 Cor. 10:31). 

St. John of Kronstadt, My Life in Christ