Al-Allaamah Rabee Bin Haadi Al-Madkhali (may Allaah preserve him) said:

”By Allaah, the one who speaks ill of Shaikh Ubaid and says that he is a Jaahil; this (person) is one following the path of the devils; he follows the paths of hizbiyyah in speaking ill of the scholars of the Salafi manhaj. Shaikh Ubaid is from the virtuous Salafi scholars and is well known for Wara, Zuhd and speaking truth, may Allaah bless you. And a man who seeks the face of Allaah does not speak ill of him, and we know of these ways (i.e. attacks against the scholars) from the hizbiyyeen.”  http://www.sahab.net/forums/index.php?showtopic=116834

Al-Allaamah Saaleh Al-Fawzaan (may Allaah preserve him) said:

None violates the honour of the scholars who are upon the truth, except one of three (people): Either a hypocrite known for (his) hypocrisy, or an evil sinner who hates the scholars because they prevent him from his sinful (acts) of disobedience, or a misguided hizbi who hates the scholars because they neither agree with his hizbiyyah nor with his deviated views. [Al-Ajwibah Al-Mufeedah page 51 and Muhaadaraat Fil Aqeedah Wad-Dawa 2/190]