What is the evidence that a woman's face is not awrah from the Almighty's saying: (and let them cast their head-coverings over their bosoms)?

It is incorrect to use the noble verse (And let them cast their head-coverings over their bosoms) as evidence for the non-obligation of covering the face; rather, it indicates its obligation. The female Companions, after the revelation of the verse, understood the obligation of covering their faces, so they proceeded to cover them with their outer garments. Aisha, may Allah be pleased with her, said: "May Allah have mercy on the immigrant women of the first generation. When Allah revealed (And let them cast their head-coverings over their bosoms): they tore their outer garments and veiled themselves with them." This indicates that veiling and covering the face are established in the authentic Sunnah, as an interpretation of the Book of Allah the Almighty, and that the female Companions applied this in obedience to Allah's command.