What is the ruling on declaring a dedication ('Waqf') without specifying its purpose or beneficiaries?

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If a person states, 'I have dedicated this' (Waqaftu hadha) and remains silent, or says, 'This is a dedicated charity' (Sadaqa mawqufa) without mentioning its path or purpose, the dedication is valid. This view is held by Ibn Hamid and aligns with the established position of Imam Ahmad. The legal basis is derived analogously from Imam Ahmad's ruling that an unconditional vow (Nathr mutlaq) becomes binding, requiring the expiation of an oath. This ruling is also held by Malik and one opinion of Al-Shafi'i, as dedicating property for a charitable purpose is an alienation of ownership accepted as an act of piety (Qurbah), thus rendering it valid when stated absolutely, similar to the validity of an 'Udhhiyah (sacrifice) or a Will (Wasiyyah).