The book Sermons to Believers consists of two volumes. The first volume is entitled Prayers, and the second volume is entitled Major and Minor Sins. These books were completed in the 1970s and have been reprinted many times since then. The late author, Mehmed Zahid Kotku, was a perfect spiritual guide who followed the path of his righteous predecessors and continued their traditions by updating them for the 20th century. The literature of supplication, which occupies a significant place in the life of the Prophet and is a sign that he never lost contact with his Lord, developed rapidly immediately after the era of bliss, either forming a large part of books or appearing as independent books. Mehmed Zahid Efendi prepared a book of daily prayers, which he recited without fail every morning after the dawn prayer in the mosques where he served as imam, together with the congregation, and emphasised the importance of prayer in the life of a Muslim at every opportunity. The first of these books points out the importance of prayer in human life and then presents a selection of distinguished and chosen prayers. The second book is entitled Great Sins and lists and explains sins that are religiously prohibited and for which there is clear evidence, as well as sins that are punishable in this world or the hereafter, and negative behaviours that are not included in the former category, which are called Minor Sins. Many books have been written by Islamic scholars on these sins, some of which have increased their number to 700, while others have limited them to seventy. The journey towards perfection in religion begins with negation (nefy) and is followed by affirmation (isbat). According to the secret of ‘the sultan does not come until the house is in order,’ the first thing that must be done is to abandon negative feelings, words and actions. The things that are displeasing to God and considered sinful must first be known and abandoned. Therefore, it is essential to read and learn about these sins repeatedly in order to be freed from them. These books have been read and compared with each other, and any previously missing or incorrect passages have been identified and corrected as far as possible. An effort has been made to ensure consistency in spelling and other technical matters. The sources of the verses, hadiths, sayings of the wise, and poems have been indicated as much as possible, and a bibliography has been added at the end of the work. The analytical index prepared for each volume has greatly facilitated the work of researchers conducting research on various topics within the book.
