My desires to you are–That you would make it your business to study Christ, his Word, your own hearts, Satan’s plots, and eternity–more than ever. That you would endeavor more to be inwardly sincere than outwardly glorious; to live, than to have a mere name to live. That you would labor with all your might to be thankful under mercies, and faithful in your places, and humble under divine appearances, and fruitful under precious ordinances. That as your means and mercies are greater than others–so your account before God may not prove a worse than others. That you would pray for me, who am not worthy to be named among the saints, that I may be a precious instrument in the hand of Christ to bring in many souls unto him, and to build up those who are brought in, in their most holy faith; and “that utterance may be given to me, that I may make known all the will of God” (Eph. 6:19); that I may be sincere, faithful, frequent, fervent and constant in the work of the Lord, and that my labor be not in vain in the Lord; that my labors may be accepted in the Lord and his saints, and I may daily see the travail of my soul.
Thomas Brooks, Precious Remedies Against Satan’s Devices