1.40. In the destruction of a family, the immemorial religious rites of that family perish; on the destruction of spirituality, impiety, indeed, overcomes the whole family.

1.35 1.44 Nihatya etc. upto anususruma. Sin alone is the agent in the act of slaying these desperadoes. Therefore here the idea is this : These ememies of ours have been slain, i.e., have been take possession of, by sin. Sin would come to us also after slaying them. Sin in this context is the disregard, on account of greed etc., to the injurious conseences like the ruination of the family and the like. That is why Arjuna makes a specific mention of the [ruin of the] family etc., and of its duties in the passage 'How by slaying my own kinsmen etc'. The act of slaying, undertaken with an individualizing idea about its result, and with a particularizing idea about the person to be slain, is a great sin. To say this very thing precisely and to indicate the intensity of his own agony, Arjuna says only to himself [see next sloka]:

When the family is destroyed, the eternal family duties are lost. And when duty is destroyed, unrighteousness overwhelms the entire family. Commentary: "When the family is destroyed, the eternal family duties perish" – When war occurs, there is destruction (diminution) of the family (lineage). From the very beginning of a family, the duties of the family, meaning its sacred traditions, sacred customs, and codes of conduct, have also been passed down through the generations. However, when the family is destroyed, the duties that have always resided with the family are also destroyed. That is, the various scriptural, sacred rites and rituals performed at the time of birth, at the time of sacraments for the twice-born, at the time of marriage, at the time of death, and after death—which are beneficial for both the living and the deceased souls in this world and the next—are lost. The reason is that when the family itself is annihilated, upon whom will the duties dependent on the family rely? "And when duty is destroyed, unrighteousness overwhelms the entire family" – When the sacred codes of conduct and sacred practices of the family are destroyed, then not adhering to duty and acting contrary to duty—meaning, not performing actions that ought to be done and performing actions that ought not to be done—this unrighteousness overwhelms the entire family, meaning unrighteousness pervades the whole family. Now, a doubt arises here: when the family is destroyed and ceases to exist, whom will unrighteousness overwhelm? The answer is this: the men capable of fighting are slain in the war; however, those who are not fit for battle, such as the children and women who remain behind, are overwhelmed by unrighteousness. The reason is that when men knowledgeable and experienced in weaponry, scripture, worldly conduct, etc., perish in the war, then there remain no one to give proper guidance to the survivors or to govern them. Consequently, due to a lack of knowledge of codes and proper conduct, they begin to act arbitrarily—that is, they do not perform actions that ought to be done and begin to perform actions that ought not to be done. Therefore, unrighteousness spreads among them.