What is the preference regarding marrying a woman from outside one's immediate lineage (an outsider or foreigner)?

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It is preferable to marry an outsider (*ajnabiyyah*) because her offspring are generally more vigorous. It is said: 'Marry the unfamiliar so that your offspring do not weaken.' Some scholars suggest that outside women are more vigorous, while cousins (*banaat al-'amm*) are more patient. This preference for outsiders stems from avoiding enmity in marriage which could lead to divorce, and if the spouse is a relative, divorce might result in the severing of kinship ties, which one is commanded to maintain.