Etymology From Arabic الله (allāh, “the deity, God”). Compare by God.
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Islam, Lifestyle, Religion An oath to emphasize sincerity or truthfulness, by God
The eldest, however, having hent in hand a bannock of bread, exclaimed, “By Allah, verily this cake was baked by a woman in her ailment!”1885, Richard F. Burton, “Story of the Sultan of Al-Yamman and his three sons”, in A Plain and Literal Translation of the Arabian Nights Entertainments, volume III, page 357:
O community of Muhammad! By Allah, if you knew what I knew, you would laugh little and weep much.1989, Malik ibn Anas, translated by Aisha Abdurrahman Bewley, Al-Muwatta of Imam Malik ibn Anas:
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Very, truly, indeed.
‘Was not the best food to him camel meat and the best drink camel milk[?]’ They said, ‘Yes, by Allah.’2007, Muhammad Saed Abdul-Rahman, The Meaning and Explanation of the Glorious Qur'an, page 7: