My husband who is 66 years, has become very impatient.

Answer

Your only option is Sabr. If you say anything, it will only become worse. While he is undoubtedly wrong, there is nothing you can do to remedy the matter. When people of the dunya become old, they move into the domain of senility. They lack patience and foresight. In this regard Allah Ta'ala says in the Qur'aan Majeed:

"We created you weak (that is in the state of infancy), then We granted you strength, then We (again) made you weak and old."

(Ar-Room, Aayat 54)

"Allah has created you, then He will cause you to die. And, from among you are those who will be returned to the age of senility ( physical and brainal infirmity) so that they know nothing after having had knowledge. Verily, Allah is Aleem and Qadeer (The Knower and The Powerful One)." (An-Nahl, Aayat 70)

On the other hand, a person who develops Taqwa and engages much in Tilaawat of the Qur'aan during his/her young days, does not become senile in old age. But when one's youth (young age) is wasted in sin and futility, then one becomes very stupid and senile during old age.