Quran is kitab (literally "book"). However, to believe Q.2:106 and Q.16:101 are referring to verses in the Quran, Hasan says, is an error. Ayah literally means 'a sign', token, or mark by which a person or thing is known and is synonymous with `alamah. It, by implication, also means 'a message, or communication sent from one person or party to another' and is in this sense synonymous with risalah. Resolving contradictions without chronology Two theories have been proposed to deal with contradictory commands of revelation without the chronology of verses and the abrogation of earlier ayat in favor of later ones: Abrogation of (later) Medinan verses, not earlier ones The Quran has been divided by scholars into those verses revealed while Muhammad was in Mecca (the Meccan surah) preaching to develop a following, and those revealed after he left Mecca to govern the city of Medina (the Medinan surah). Sudanese Islamic scholar Mahmoud Mohammed Taha has advanced the idea that the Meccan surah contain "the basic and pure doctrine of Islam", and should form the "basis of the legislation" for modern society. These Meccan verses give more prominence to the position of women and praise other prophets and their communities — i.e. Jews and Christians. Taha argues that the Medinan surah, though revealed later in the mission of Muhammad, are not corrections of Meccan revelations but contain specialized commands/doctrine, "compromises" for the political climate, which while appropriate for their time are not eternal and are not necessarily appropriate for the 20th or 21st century. Replace abrogation with application of commands according to circumstances Ahmad Hasan argues that since the Quran is valid for eternity, the solution to any contradictions found within it is not to abrogate earlier verses, but to recognize that Qur'anic revelations varied to keep "pace with the changing conditions and environment" and must be studied and applied to their "historical context". In the case of the Meccan surahs that ask "Muslims to be patient and to tolerate the aggression of the infidels" (for example: Q.2:109; Q.6:106; Q10:109; Q15:85; Q29:46), and which conflict with the Medinan Sword Verse (Q.9:5) that calls on Muslims to attack "the infidels and kill them wherever they are found"; neither is a pure/basic doctrine, nor a temporary tactic. The Meccan surahs were revealed when the Muslims were/are weak and could not retaliate against aggression, Medinan surahs when Muslim were/are strong. The proper command