"Be patient at all times and in all places, for patience leads to righteousness, and righteousness leads to Paradise. Do not become angry and furious, for those two emotions lead to wickedness, and wickedness leads to the Hellfire." 

Source: Biography of Imam Sufyaan ath-Thawri by Salaahud-Deen ibn Ali ibn Abdul-Maujood

 

“The Salaf were never like this; they never used to claim leadership, or sit at the head of the gathering until they had sought this knowledge for thirty years, and you act haughty in front of those who are older than you. Get up, I never want to see you even come close to my circle.”

{Al-Bayhaqi, Al-Madkhal ila Al-Sunan Al-Kubra 2:74}

Imam Sufyaan (rahimahullah) wrote in a letter:

"Improve your secret and private life, and Allah will improve your public and social life. Make matters well between you and Allah, and Allah will make matters well between you and people. Work for the Hereafter, and Allah will be enough for you in your worldly concerns."

Source: Biography of Imam Sufyaan ath-Thawri by Salaahud-Deen ibn Ali ibn Abdul-Maujood

One Friday, Sufyaan saw a man who, while the ruler was delivering the Friday sermon, was trying to get as close as possible to the pulpit. Sufyaan later said to the man:

 "You disturbed me when you tried to get closer to the pulpit. Were you not afraid that you would hear some strange remark from the ruler and that it would then become obligatory upon you to refute him?" The man said: "Was it not said: 'Come closer and listen attentively (to the sermon)?" Sufyaan said: "That command applied to Abu Bakr radiallahu anhu, Umar radiallahu anhu, and the (other rightly guided) Khaleefahs. As for the rulers, stay as far away as you can from them, so that you do not hear their speech or see their faces."

Source: Biography of Imam Sufyaan ath-Thawri by Salaahud-Deen ibn Ali ibn Abdul-Maujood

Yousef ibn Asbaat reported that Sufyaan once said:

 "If these kings invite you to visit them, send them this message: 'Say (O Muhammad Salalahu Alayhi wa Salam): He is Allah, (the) One (i.e. the first Verse of "Chapter Purity" of the Noble Quran)." But do not go to them, for being in close proximity to them corrupts the heart."

Source: Biography of Imam Sufyaan ath-Thawri by Salaahud-Deen ibn Ali ibn Abdul-Maujood

Al-Waleed ibn Muslim related that Sufyaan said: 

"None should advise the ruler to do what is right save a man who knows what he is commanding him to do and knows what he is forbidding him from; who is gentle when he commands, and gentle when he forbids; who is just regarding that which he commands, and just regarding that which he forbids." And Abdur-Rahman ibn Mahdee said: "Even though Sufyaan was stern with rulers, I never once heard him curse a ruler."

Source: Biography of Imam Sufyaan ath-Thawri by Salaahud-Deen ibn Ali ibn Abdul-Maujood

Khalf ibn Ismaa'eel Al-Barzaanee reported that he heard Sufyaan ath-Thawri said,

"Acquaint yourself with fewer people, and as a result, you will backbite less (frequently)." 

Source: Biography of Imam Sufyaan ath-Thawri by Salaahud-Deen ibn Ali ibn Abdul-Maujood

Sufyaan ath-Thawri said,

"Whenever I spoke contrary to the desires of any man, he, regardless of who he was, would inevitably become furious with me. The people of knowledge and piety have departed."

Source: Biography of Imam Sufyaan ath-Thawri by Salaahud-Deen ibn Ali ibn Abdul-Maujood

Al-Firyaabee reported that Imam Sufyaan ath-Thawri (rahimahullah) said,

"The only situation which I feel is analogous to the departure of a believer from this world is the departure of a baby from its mother's womb, from the gloominess (inside of its mother's womb) to the spirit (and freshness) of the world."

Source: Biography of Imam Sufyaan ath-Thawri by Salaahud-Deen ibn Ali ibn Abdul-Maujood

Imam Sufyaan once wrote in a letter to one of his Brothers:

"....Beware of doing that which will spoil your deeds, and know that it is showing off that spoils a person's deeds; and if it is not showing off then it is conceitedness- for you to imagine that you are better than one of your Muslim brothers, when in reality he performs more good deeds than you do; or perhaps he stays further away from that which Allah has prohibited than you do; or perhaps he performs his deeds with purer intention that you do. And even if you are not conceited, beware of developing a love for praise. Be ever so careful not to come to love other people's praise of your good deeds, or the respect they feel for you and bestow upon you because of your good deeds. And beware of desiring that others should help you in your personal affairs just because they have become impressed by your good deeds. You surely claim (as does everyone else), after all, that you are doing good deeds only for the sake of Allah, well, then turn that claim into reality...."

Source: Biography of Imam Sufyaan ath-Thawri by Salaahud-Deen ibn Ali ibn Abdul-Maujood