What is the basis for the obligation of financial support (Nafaqah) for poor parents and children?

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The foundation for the obligation of support for poor parents and children rests upon the Book (Quran), the Sunnah, and scholarly consensus (Ijma'). The Quran obligates payment of wages for a wet nurse (Quran 65:6) and mandates that the father provide sustenance and clothing for the mother during suckling (Quran 2:233). Furthermore, the command to honor parents (Quran 17:23) includes providing support when they are in need. The Sunnah confirms this through the Prophet's instruction to Hind to take what suffices her and her child by recognized means, and his saying that a man's best earning is his own, and his child is part of his earning. Consensus exists among scholars that the support for poor parents without means or earning capacity is obligatory from the son's wealth, and similarly, consensus holds that parents must support their financially dependent minor children.