For the mental level of the Ummah to reach such a standard...
For the mental level of the Ummah to reach such a standard, as to be able to lead the newly-established Islamic movement and to protect it from any hazard, after the Prophet. After the Prophet's demise, this condition unfortunately did not materialize we could not identify all the reasons for this. However we could present the following remarks: The wide-ranging and comprehensive revolution in the heart of a nation would not occur within one or, two days, nor a year or ten years.
Within a short time this could not happen at all. Rather, in order to keep the very foundation of the revolution intact, a capable individual or individuals would be required to handle the affairs of the nation after the demise of the revolution leader, and who could keep the nation safe and sound against poisonous indoctrinations until the older generation could pass and the new generations could come forth with the Islamic etiquette.
If this did not occur, then a great number of Muslims would withdraw from their ideology as soon as the founder of the revolution passes away. Besides, out of all divine movements, Islam possessed another trait which made it urgent for such capable individuals to exist: Islam found its way among the most retarded and backward nations of the world who were living in pure depravity.
Out of religious traditions they were only familiar with the Hajj ceremony which they had inherited from their ancestors (and that too mixed with superstitions). Neither Musa' teachings, nor Christ's instructions had penetrated their land and the majority of the Hijaz population was deprived of such religious teachings. On the other hand, they were under the influence of the customs of the age of Ignorance. The religious reform in its initial state, might not look difficult among such nations.
However, its continuity among people whose spirits are filled with negativity, is quite difficult. Such a continuity needs persistent care so that such nations do not go astray.
The distressing and depressing events of the wars of Uhud and Hunain in which the combatants left the Prophet alone on the arena, showed there were few genuine Muslims who wanted to sacrifice everything for the Islamic movement, and that the members of the community had not mentally progressed to the stage where they could be left guideless. We see that after the Prophet's demise, such an Ummah divided themselves into seventy three sects.