Validity of Hajj for a boy reaching puberty or a slave being manumitted before or at Arafah while not being in the state of Ihram for Hajj?

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If a boy reaches puberty or a slave is manumitted before or at Arafah, and they enter the state of Ihram and perform the standing (wuquf) at Arafah, completing the rituals, it suffices them for the obligatory Hajj (Hajjat al-Islam). This ruling is held without known dispute because nothing essential of Hajj was missed, nor was anything performed before its obligation set in. This is supported by the fact that the individual reached the standing having the legal capacity (free and mature), making it valid, similar to if they had entered Ihram at that very moment. This view is held generally by scholars, aligning with the position attributed to Ibn Abbas.