Is buying a wedding dress and dedicating it as an ongoing charity (sadaqah jariyah) from which people benefit considered a continuous sadaqah jariyah after death and a means of expiating sins? Is sacrificing an animal for Eid al-Adha on behalf of the deceased permissible, provided it is distributed only among Muslims? And what is the specific supplication to be recited at the time of slaughter?

It is permissible for Sadaqah (definition) Jariyah (ongoing charity) to be given on behalf of both the living and the deceased. It is also permissible to make a garment Sadaqah Jariyah, such that its rent is collected and spent on good causes. The garment is considered Sadaqah Jariyah for as long as it is being utilized. Charity is a means for the forgiveness of sins. Sacrificing an Udhiyah (definition) (sacrificial animal) on behalf of the deceased is a matter of scholarly disagreement, with the closer opinion being that it is disliked. As for sacrificing on behalf of the living, it is permissible only with their permission. It is permissible to stipulate the method of distributing the Udhiyah, or to stipulate that it should not be distributed to non-Muslims.