"The Messenger of Allah [SAW] cursed the one who consumes Riba, the one who pays it, the one who witnesses it and the one who writes it down; the woman who does tattoos and the woman who has that done; and forbade wailing (in mourning), but he did not say that its doer is cursed."
The Book of Adornment - Sunan an-Nasa'i 5105
"The Messenger of Allah [SAW] cursed the one who consumes Riba, the one who pays it, the one who witnesses it and the one who writes it down; the woman who does tattoos and the woman who has that done; and forbade wailing (in mourning), but he did not say that its doer is cursed."
Commentary on the Prohibition of Riba
The comprehensive curse upon all participants in usurious transactions demonstrates the gravity of this sin in Islamic law. The consumer, payer, witness, and scribe are all equally condemned, indicating that facilitation of haram is itself haram.
Scholars explain that this comprehensive condemnation serves to completely eradicate the system of riba from Muslim society, leaving no room for participation at any level.
Commentary on Tattooing
The prohibition of tattoos falls under the general principle of preserving Allah's natural creation. The woman who performs tattoos and the one who receives them are both cursed, indicating the mutual responsibility in this alteration of Allah's creation.
Classical scholars note that this prohibition applies to permanent markings that change the natural form, as they constitute a rejection of Allah's perfect creation.
Commentary on Wailing
The distinction in wording regarding wailing is significant. While the Prophet forbade it, he did not pronounce a curse upon its practitioners, indicating a difference in severity between this and the previous prohibitions.
Scholars explain that wailing represents excessive mourning that contradicts Islamic patience and acceptance of divine decree, though it does not reach the level of major sins like riba.