Muhammad's religious career is often divided into two periods: the Meccan Period which lasted for thirteen years, from the start of his revelations to his emigration to Medina; and the Medinan period, which lasted the remaining ten years of his life.
The Meccan Period is characterized by the more elliptical and otherworldly portions of the Qur'an, and by the story of the rejected and persecuted prophet. Had the assassination plot against him in 621 succeeded, his religious career would have been similar in broad outline to that of Jesus.
However, Muhammad escaped the trap set for him and went to live in the oasis of Medina. There he evolved from the charismatic head of a small group to the political and spiritual director of a large community. For the first time he had to wrestle with the challenges of creating a new society. The Qur'an continued to be revealed to him, but the focus of the message broadened now from the purely spiritual to include the more temporal issues of community building, lawmaking, and social institutions. Muhammad also came under formal military attack for the first time in Medina. Consequently, the Qur'an and Muhammad's teaching also focused on delineating the concept of the just war. Formal permission to fight is first applied in the Medinan Period:
"They will question you concerning the holy month, and fighting in it. Say: 'Fighting in it is a heinous thing, but to bar people from God's way, to disbelieve in Him and the Holy Mosque and to expel its people from it - that is more heinous in God's sight; and persecution is more heinous than fighting." (Qur'an 2:217)
Through most of the Medina period, the Muslim community was in mortal danger and surviving in a defensive mode. Between 624 and 627 especially, the Muslim community was often quite literally fighting for its life. It is no accident that the concepts of jihad and martyrdom were developed at this time.
Though the Qur'an takes on more temporal issues in the Medinan Period, it does not abandon the notions of spiritual striving and God consciousness that were hallmarks of the Meccan Period. Even the concept of defensive warfare is placed within the larger concept of jihad as striving for what is right. Though jihad might involve bloodshed, it has the broader meaning of exerting an effort for improvement, not only in the political or military realm, but also in the moral, spiritual, and intellectual realms. Muhammad is often cited in Islamic tradition for calling the militant aspect of jihad the "minor" or "little" jihad, while referring to the improvement of one's self as the "greater" jihad.
Other revelations and rulings during this period concerned the proper treatment of prisoners of war and non-combatants, the sanction against killing innocent civilians, and the respectful treatment of enemy corpses (in contrast to the custom of the time, which was mutilation.) The wanton destruction of property or agricultural resources was put off limits too.
With many of the billion-plus Muslims living in poverty or oppression, Islam has become a rallying point for independence movements worldwide. Since jihad and martyrdom were placed within a religious context during the Medinan period, some of these independence movements have deployed the same concepts as sanctified tools for motivating combatants in the face of overwhelming odds. Thus, some seek a military solution to their political aspirations.
At the far end of the spectrum lies a fairly recent tendency to justify acts of terror with quotations from the traditions of Islam. This exercise in legal sleight of hand, placed beyond the pale by all except the terrorists themselves, has bred enormous doubt throughout the world about the essentially peaceful nature of Islam.
Especially since the tragic events of September 11, most religious scholars around the world have rejected these interpretations as spurious. Rather, they have re-emphasized the Prophet's saying that "the true jihad is only that which exalts God's word, which is truth." The Qur'an condemns as an ultimate act of blasphemy actions that attempt to dismantle the very fabric of existence by destroying and spreading ruin on the Earth. Elsewhere it states that God has willed Muslims "to be a community of moderation." (Qur'an 2:143)