Does the husband bear the sins and transgressions of his wife despite his advice and guidance to her? Is the niqab obligatory for women? And is the husband sinful if his wife does not wear the niqab?

The fundamental principle is that no individual bears the sin of another, as Allah Almighty says: "And every soul earns not [anything] except for itself, and no bearer of burdens will bear the burden of another."

However, a husband is responsible for his wife, and it is incumbent upon him to oblige her to perform her duties and prevent her from forbidden acts. If he neglects his guardianship, he will be held accountable before Allah. But if he fulfills his obligations, then he will not be harmed by any sin committed by his wife.

Regarding the niqab, if the husband believes it is obligatory, then he must oblige his wife to wear it, and she must obey him in this matter, even if she believes it is not obligatory.