What is the definition of altering Allah's creation, and what practices fall under it, such as using cosmetics, plucking eyebrows, and using moisturizing creams, and are they permissible?

Summary:

The prohibition against altering Allah's creation is mentioned in the Quran and Sunnah, and it includes tattooing, plucking eyebrows (namṣ), teeth filing (tafluj), and hair extensions. The Prophet, peace and blessings be upon him, cursed those who perform these actions.

These changes are forbidden if they are for beautification and remain permanent. However, what is temporary, or for treatment, or to remove a transient defect is not included in the prohibition.

Plucking eyebrows (namṣ) is considered permanent because the hair grows back and is plucked continuously, thus making namṣ a persistent habit.

Exempted from the prohibition is what is for treatment, or to remove a transient defect, or temporary adornment that does not alter the original creation, such as kohl and henna.