What is the meaning of "the one who safiha himself"?

Imām Ibn al-Jawzī (d. 597/1201) summarized the scholars' opinions in his book "Zād al-Masīr" as follows:

1. "Except the one who makes a fool of himself." [al-Akhfash, Yūnus].
2. "Except the one who destroys himself." [Abū ʿUbaydah]
3. "Except the one whose self is foolish." [al-Farrāʾ, Ibn Qutaybah]
4. "Except the one who is ignorant concerning his own self and does not reflect upon it." [This is the preferred view of al-Zajjāj]