What is the ruling on a man looking at a non-related woman without a specific legal reason?

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Looking at a non-related woman without a valid reason is prohibited concerning her entire body, according to the apparent position of Ahmad. Ahmad stated that a man may not eat with his divorced wife because she is a non-related woman (ajnabiyyah) to whom looking is not permissible, questioning how he could eat with her or look at her hand. The view held by the Qadi is that looking is forbidden concerning everything except the face and the two palms, as these are considered outside the definition of 'awrah in this context. The basis for this allowance is the verse: "and not to display their beauty except what appears thereof" (Quran 2:31), which Ibn Abbas interpreted as the face and the two hands. Aisha narrated that when Asma bint Abi Bakr entered upon the Prophet, peace be upon him, wearing thin clothes, he turned away and instructed her that once a woman reaches puberty, nothing of her should be seen except this and this, gesturing to her face and hands. This is argued because these parts are not considered 'awrah that necessitates covering when there is no suspicion.