Imam Abdul Wahab al-Sha’rani (may Allah have mercy on him) said,
“My master ‘Ali al-Mursifi, may Allah have mercy on him, used to say: One of the signs of the novice’s (murid’s) wretchedness in this world and in the next is his taking lightly the Shaykh’s anger with him and not contemplating the urgency of hastening to make up with him and bringing himself under the banner of his obedience. Some people took lightly their Shaykh’s anger with them and they never succeeded after that: neither at the hands of their Shaykh nor at the hands of anyone else.”
P.S. Two books of Imam al-Sha’rani are included in the Curriculum of Tasawwuf recommended to the seeker’s by Hakim al-Umma (may Allah have mercy on them).
May Allah Tabaraka Wa Ta’ala protect us from the anger of his Walis – which matter of fact means the wrath of ALLLAH, too. Ameen.