Undoubtedly, the heart leans towards those who are kind and gentle. It was said a long time ago: "Make your face happy and your words gentle, and you will be more beloved to the people than those who give them a gift". The one calling to the religion of Islam and dealing with other people has the utmost need to gather the people around him, and cause their hearts to lean towards him so that they will listen to him. Adorning himself with kindness and gentleness helps to achieve that goal with the grace of Allah.
Ibn Katheer, At-Tabari, As-Syooti and Other Historians. The four Rightly guided Caliphs (Khaliph's) Abu Bakr As-Sideeq, Umar ibn Al-Khattaab, Uthmaan Ibn 'Affaan and Ali Ibn Abi Taalib. The Biography of Umar Ibn Abdel-Azeez who is regarded as one of the Rightly Guided Chaliphs is also included in this book.
Author: Imam Ibn Kathir
A monumental work discussing the Makkan period of the Prophet's life, and a refutation of Orientalist attacks.
Author: Muhammad Mohar Ali - Mohammed Mahr Ali
An incisive, thoroughly research and above all informative discourse on the subject of Prophet Muhammad in the Bible.
Author: Kais Al-Kalby
Warning to those who have abandoned prayers
Author: Khaalid Abu Saalih - Khalid Abu Salih
Publisher: Daar Al-Watan
Source: http://www.islamhouse.com/p/1327
Introduction to history of polytheism and monotheism: Allah (glory be to him) created all people as Muslims and monotheists but devils came to them and changed and distorted their religion. Allah said in a qudsi hadith, “I created all my slaves as haneefs (monotheists), but the devils came to them, made them deviate from their religion, forbade them that which I had permitted to them, and commanded them to join partners with me for which I has given no authority.” As soon as people commit a type of polytheism, Allah sends his prophets to call them to the suitable type of monotheism.
Author: Ameen Al-Ansaari
Publisher: A website Knowing Allah : http://knowingallah.com