Narrated Sa`d bin 'Ubaida:

A man came to Ibn `Umar and asked about `Uthman and Ibn `Umar mentioned his good deeds and said to the questioner. "Perhaps these facts annoy you?" The other said, "Yes." Ibn `Umar said, "May Allah stick your nose in the dust (i.e. degrade you)!' Then the man asked him about `Ali. Ibn `Umar mentioned his good deeds and said, "It is all true, and that is his house in the midst of the houses of the Prophet. Perhaps these facts have hurt you?" The questioner said, "Yes." Ibn `Umar said, "May Allah stick your nose in the dust (i.e. degrade you or make you do things which you hate) ! Go away and do whatever you can against me."