Yoosuf Ibn Asbaat (rahimahullaah) said: ”Purification of the intention from (what) corrupts it is harder upon the performers of (acts of worship) than prolonged striving (worship)” [Jaami al-Uloom Wal-Hikam: page:14]
Khaalid Ibn Mi’daan (rahimahullaah) said: ”if a door of good is opened for one of you hurry towards it; because he does not know when it will be closed. [Hilyatul Awliyaa: 5/211]
In The Name of Allaah, The Most Merciful, The Bestower of Mercy
Imaam Muqbil (rahimahullaah) said: ”As for my Ikhlaas, it is weak.” He said: ”We fear Riyaa for ourselves and we are not safe from it; we fear self-amazement for ourselves and we are not safe from it.” [Source: Al-Fataawa Al-Hadeethiyyah.1/ 31]
In The Name of Allaah, The Most Merciful, The Besower of Mercy
”When death approached Amr Bin Qais Al-Malaa’iy (rahimahullaah) he wept; so his companions said to him: ”What makes you weep about the worldly life, for by Allaah you have been modest during your life.” He said: ”By Allaah, I am not weeping over the worldly life, rather I weep fearing that I will be deprived of the goodness of the hereafter.” [[Shu’ab Al-Imaan 1/508]
In The Name of Allaah, The Most Merciful, The Bestower of Mercy
When a Bedouin heard the saying of Allaah [فَوَرَبِّ السَّمَاء وَالأرْضِ إِنَّهُ لَحَقٌّ مِّثْلَ مَا أَنَّكُمْ تَنطِقُونَ] ”Then, by the Lord of the heaven and the earth, it is the truth (i.e. what has been promised to you), just as it is the truth that you can speak”[Dhaariyaat Ayah: 23]; so he (i.e. the bedouin) said: ”Who angered the Mighty and Majesty so that He made an oath?!” [At-Tawwaabeen: 279]
Shaikhul Islaam Ibn Taymiyyah (rahimahullaah) said:
”The heart does not cease being put to trial until the slave makes all his religion for Allaah.” [Al-Fataawaa: 10/545]
Imaam Ibnul Qayyim (rahimahullaah) said: A slave (of Allaah) will not (truly actualize the statement) ”you alone we worship (O Allaah)”, except by way of two fundamental principles: The first of them is to follow the Messenger (sallal-laahu-alayhi-wasallam) and the second is sincerity to the (only true object) of worship (i.e. Allaah) [source-page: 68تهذيب المدارج ]
Maalik Bin Deenaar (rahimahullaah) said: ”When a slave (of Allaah) seeks knowledge to act upon it, it withholds him (from evil and guides him towards good). And when he seeks it for other than acting upon it, it increases him in boasting.”
[source: اقتضاء العلم العملpage:33]
Imaam Ahmad said: ”When a man knows himself, the speech of the people is of no benefit to him.” [Siyar: 11/211]
It reached Ibraaheem Al-Harbee (rahimahullaah) that a people who sit with him considered him more virtuous than Imaam Ahmad Bin Hanbal (rahimahullaah); so he said to them: ”You have wronged me by considering me more virtuous than a man whom I am neither similar to nor have I reached (his status) in any affair. I swear by Allaah, you will never hear anything of knowledge (from me), so do not come to me after today. [Siyar A’laam Nubulaa: 13/364]