Is it obligatory in our true religion to consider the future ratio of children and the preservation of lineage in marriage?

Scholars have differed regarding the consideration of lineage compatibility (kafa'ah) in marriage, and the preponderant opinion is that the only compatibility that matters is in religion. A guardian should not reject someone of good character and religious commitment due to social differences, because doing so promotes good and righteousness. One must be wary of letting these differences become a cause for pre-Islamic tribalism ('asabiyyah), for the measure of superiority is piety before Allah, in accordance with His saying: "O mankind, indeed We have created you from male and female and made you peoples and tribes that you may know one another. Indeed, the most noble of you in the sight of Allah is the most righteous of you. Indeed, Allah is Knowing and Acquainted."