Marriage is incompatible with greatness

 Ksav Sofer (Vayikra 10:1): And they offered before G‑d an unauthorized fire which He had not commanded them. Question: The Tanchuma (Achrei Mos #8) says that Aaron’s sons died because they didn’t get married and didn’t have children. Furthermore it says that they walked behind Moshe and Aaron and said, “When are these old men going to die so that we can take over the leadership of the community?” It is necessary to understand this medrash since it does not seem to fit in with the Torah which gives the explicit reason for their death as being punishment for offering an unauthorized fire before G‑d?  It is also astounding that these righteous men - who were in fact greater than Moshe and Aaron according to Rashi (10:3) – should transgress G‑d’s command and not fulfill the mitzva of having children and also that they would speak in such an arrogant manner – “when are these old men going to die?” Answer: It appears to me that the reason that they didn’t get married is that they saw that Moshe’s children did not turn out properly as is well known. If Moshe’s sons were not fit then they felt that a lesson could be learned that surely would apply to the masses. They ascribed the failure of Moshe’s children to the fact that Moshe was constantly preoccupied with the problems of the community and therefore he didn’t have the ability to properly supervise his children. 

 Avraham ben haRambam (Hamaspik L’avodas Hashem)   Regarding a person who is considering marriage before becoming proficient in Torah study the gemora (Kiddushin 29b) expresses amazement at such an absurd idea by saying with a millstone on his neck, he is going to study Torah?! When one scholar refrained from getting married (Yevamos 63), he explained his reason “My desire is for Torah” Yakov did not get married  until he was 83 years old. Similarly we see that Eliyahu and Elisha never got married. Here it is relevant to note the fact that all the prophets  broke off all contacts with their families as we see when Elisha decided to follow after Eliyahu.  It seems to me that in order not to nullify the mitzva of having children that we find that some acted like Moshe who married and had children before separating from his wife. And also because they didn’t want their conduct to become followed by everyone.