Then, Islam spread among the tribes and villages near Makkah because of the wise Da`wah and what they heard from the Companions of the Prophet (peace be upon him) who embraced Islam and responded to the Prophet. The Prophet (peace be upon him) used to present himself to the tribes at the pilgrimage season every year, calling them to Islam and asking them to support and defend him until he could convey Allah's Message. By Allah's Will, AlAnsar (may Allah be pleased with them) accepted the Prophet's call and agreed to support him. At first, six of them met the Prophet (peace be upon him) near AlJamrah; they accepted the Prophet's call and pledged to convey the Prophet's message to their people in Madinah. Hence, many of their people embraced Islam. The following year, twelve people of AlAnsar, including the six who had met with him previously, came to the Prophet (peace be upon him). As`ad Ibn Zurarh (may Allah be pleased with him) and some of his tribe, AlKhazraj, and two people (or three, according to some narrations) from AlAws met the Prophet (peace be upon him) on one of the days of AlTashriq (11th, 12th and 13th of Dhul Hijjah). He (peace be upon him) recited the EverGlorious Qur'an to them and they pledged allegiance to him (peace be upon him) and embraced Islam. They returned to their people and called them to Allah; hence, Islam spread among AlAnsar, who all entered Islam except a few. After that they decided to invite the Prophet (peace be upon him) to migrate to them in order to support and save him from the harm of the polytheists of Makkah.
After the first meeting that was at Al`Aqabah, the Prophet (peace be upon him) sent Mus`ab Ibn `Umayr with them to teach the people about Islam in Madinah. He called the people of Madinah to Islam and taught them about it. Hence, Islam spread among them and many people embraced Islam at his hands, including the two masters of AlAws, Sa`d Ibn Mu`adh and Usayd Ibn AlHudayr. Because of their conversion to Islam, many people among the tribe of AlAws accepted the new religion. Also, Islam spread among the tribe of AlKhazraj when As`ad Ibn Zurarh, Sa`d Ibn `Ubadah, and others embraced Islam. The following year, seventy people of AlAnsar (or seventythree, according to some narrations) went to the Prophet (peace be upon him) and pledged allegiance to him, and promised to support and defend him. This meeting was in the presence of the Prophet's uncle, Al`Abbas Ibn `Abdul Muttalib (may Allah be pleased with him). The Prophet (peace be upon him) permitted the Muslims to migrate to Madinah. Afterwards, he (peace be upon him) migrated to Madinah and called people there to Islam. Similarly, those who embraced Islam from among the tribes, such as Abu Dhar Al Ghifary and `Amr Ibn `Absah AlSalami, called their people to Allah and spread Islam through Da`wah.
Then, Allah (Exalted be He) prescribed Jihad in three stages. First: He (Exalted be He) permitted Muslims to perform Jihad. Second: He (Exalted be He) ordered them to fight those who fought against them and to stop any fighting with those who had stopped fighting against them. Third: He (Exalted be He) legislated two types of Jihad; defensive and offensive. Any of these three stages can be used according to the circumstances that Muslims experience. If they are strong, Jihad with its two types will be obligatory; while if they are weak, the defensive Jihad only will be obligatory.
As we mentioned before, the main goal of Jihad is to spread Islam, bring people out from the darkness into the light, remove obstacles from the way of Da`wah, and put an end to the corrupt people who obstruct Da`wah and prevent the Du`ah from conveying their message. Hence, Allah (Exalted be He) legislated Jihad to pave the way for Da`wah and to bring people from darkness into light, and from the trap of oppression and the abyss of depravity into the justice of Islam and the glory of guidance. The Prophet (peace be upon him) and his honorable Companions
and those who followed them adopted the way of Da`wah successfully. Hence, Islam spread through sound Islamic Da`wah and through Jihad that supported and maintained it when it faced some obstacles. The Muslims managed to expel the Romans from AlSham (the Levant) and to seize the Persian empire. Because of sincere Da`wah and Jihad, Islam spread in Yemen and among different tribes in the Arabian Peninsula. Many obstacles were also removed from the way of Da`wah. Indeed, the spread of Islam through Da`wah was the origin and the basis whereas Jihad with swords was the supporting element and the defender against the corruption of those who obstructed the way of Da`wah.
Through Jihad and Da`wah, many countries fell into the hands of the Muslims. Many people may not accept the Da`wah, as it contradicts their own wishes and is contrary to their prohibited desires and oppressive leadership. Hence, Jihad came to suppress these people and those like them, and to remove them from the way of Da`wah. In a word, Jihad supports the Da`wah, achieves its objectives, and helps the Du`ah to perform their duty .
1) An individual duty (Fard `Ayn; i.e. an act that is obligatory on every individual), or 2) a collective duty (Fard Kifayah; i.e. a duty which, if performed by some, others are exempted from the obligation; but, if none performs it, all will be sinful). Da`wah becomes an individual duty when there is none to enjoin good and forbid evil. If you are in a country or a place in which none enjoins good and forbids evil while you have the necessary knowledge that enables you to perform Da`wah, you will be obliged to perform Da`wah i.e. to guide people to Allah's Right Way, enjoin them to do good and forbid them from evil. If a sufficient number of qualified people can perform Da`wah and guide people, it is only a confirmed Sunnah (Sunnah Mu'akkadah i.e. highly recommended, as the Prophet kept on performing it all the time) and not obligatory for others to do. Similarly, Jihad is a collective duty, when there is a sufficient number of people doing it. If there is no sufficient number of people, Jihad and Da`wah become obligatory on every Muslim,