Question: Even though the Prophet of Islam himself also was on the right path, and guided the Muslims to follow it, why did he say during Prayers: Guide us towards the right path? According to terminology is it not something already achieved?
Answer: Where existence with all its phenomena (whether it is physical or intellectual) is declining and changing. As the way the birth of a phenomenon gets formation with a cause and because of special conditions. In the same way for the execution and continuance of its existence special conditions and arrangements are necessary, which will put on him the dress of continuity and life and will prevents its decline and destruction.
Directly the subject of guidance is also under the same rules. A special care (foresight) and conditions are required for guidance, whether of an individual or society for life and its continuance. Otherwise it is possible that a guided person may be diverted from the right path and after the guidance again he may go astray.
Therefore, an individual and a group by way of guidance may have acquired great and distinguished status, but its future is ambiguous. It is up to them to take the benefit of the present situation and present themselves in the court of Allah and with sincerity invocates that He may continue this blessings (of guidance) which is prone to changes and prey to decadence and destruction in all the periods of his life.
Thus if a guided person says, “O Allah! Guide us towards the straight path,” the meaning is, “keep us steadfast on it and make that blessing permanent for us.”
The great commentator of Islam, Allamah Tabarsi while presenting a parable in Majmaul Bayan says: And such parables of interpretations are many with us. When you feel that your beloved guest slowly wants to draw his hand away from food immediately you tell him: “Please continue eating”, then he continues. This means that you continue doing that work.1