What did the Prophet Muhammad (saw) encourage those who had not yet slaughtered their sacrifice for `Id al-Adha to do?
 Narrated Jundub:                     I witnessed the Prophet offering the `Id prayer (and after finishing it) he delivered a sermon and said, "Whoever has slaughtered his sacrifice (before the prayer) should make up for it (i.e. slaughter another animal) and whoever has not slaughtered his sacrifice yet, should slaughter it by mentioning Allah's Name over it."