The second Portion we read today begins with the words: VAYELECH MOSHE, “And Moshe went”. The Torah does not say where he went. (Deut. 31,1) In the very next verse Moshe says he is 120 years old and: LO UCHAL OD LATZET VELAVO: “I can no longer go out and come in…”. When Moshe says he can no longer go or come, Rashi explains, it could be understood in two ways. It can mean that because of his advanced years he is physically unable to get around. It can also mean he no longer has the authority from Hashem to lead the people.
A Biblical commentary explains, that is why the Torah states in the first verse: VAYELECH MOSHE, “And Moshe went”. He walked around demonstrating that physically he is still sound but since Joshua was appointed his successor and was given the leadership position, Moshe can no longer act in that capacity.
The message is that a person should know when it is time to give up his position and let someone else take over the reign. It is to be regretted that many people of authority hold on tenaciously to their positions and instead of continuing the good service they provided previously, their efforts begin to deteriorate and they do more harm to the cause than good.