Allah, the Wise, has said:
فَإِنَّ خَيْرَ الزَّادِ التَّقْوَى وَ اتَّقُوْنِ يَـا أُُولِي الأََلْبَابِ
"But the best of provisions is right conduct. So fear Me, O' ye that are wise." 
Imam Ali (as) said:
لاَ يُقَلَّلُ عَمَلٌ مَعَ تَقْوىً.
"No deed, if accompanied by piety, is trivial." 
Special taqwa is acquired by refraining from prohibited and dubious things, whereas general taqwa is acquired out of fear of punishment and the fire of Hell.
Taqwa is similar to the water of a river that flows by the trees growing along its banks, each tree benefiting from it in the measure of its tenderness, covetousness and essence. Although people benefit from piety according to their knowledge, perception and level of faith, their levels of piety differ in deeds and sincerity. In reality, piety is absolute obedience without any transgression, and (it is) knowledge without any ignorance. It becomes the cause for the acceptance of one's (good) deeds and makes one, who comes to possess it, distinguished and pre-eminent.
1 – The Incorrect Piety
Once, during the era of the Noble Prophet (sa), three ladies approached him to complain about their husbands.
The first lady complained: "My husband has stopped eating meat."
"My husband has abandoned the use of perfume," the second one protested.
The third lady complained that her husband did not have intimate relations with her.
(By behaving in this manner, the husbands had desired to practice piety and abstinence).
This disturbed the Noble Prophet (sa) so much that as he came out of his house, he did not even put on his cloak properly and thus, it dragged along the ground behind him.
Climbing the pulpit before a gathering of the people, he praised Allah, and said: "Why is it that some of my companions do not eat meat, they do not apply perfume and they do not have intimate relations with their wives? O' Muslims! Do know that I too eat meat, make use of perfume and am intimate with my wives. This is my tradition and one who distances himself from my tradition is not from me."
In this manner, the Noble Prophet (sa) destroyed the foundations of incorrect piety and condemned its advocates.
2 – Abu Dharr
Abu Dharr said: "My provisions and savings during the time of the Noble Prophet (sa) had always been three kilograms of dates. As long as I live, I shall never seek to possess more than this quantity."
Ata says: I noticed Abu Dharr offering prayers in an old garment. "O' Abu Dharr! Don't you have a better garment?" I asked him.
"If I had one, you would have seen me in it," he replied.
"But for a period, I had seen you with two outfits," I said.
"I gave the other one to my nephew, who was in greater need than me."
"By Allah! You are needy yourself," I exclaimed.
He raised his head towards the sky and implored, "Indeed! O' Lord! I am in need of Your forgiveness."
He then turned to me and continued, "It appears that you have come to regard this world as something very important and significant. In addition to this garment that you presently see on me, I have one more garment which is exclusive for the mosque, some goats which provide me with milk, some food, a wooden case in which I carry my belongings and a wife who relieves me from the troubles of cooking; what bounty could be greater than what I possess?"
Some people suggested to Abu Dharr, "Do you not desire to purchase properties for yourself as the others have done for themselves?"
"What need do I have to become an aristocrat or a nobleman?" he replied. "A drink of milk and water every day and a (small) amount of wheat in a week are quite sufficient for me!"
3 – A Drunkard is not to be Trusted
Isma`il, the eldest son of Imam Sadiq (as), had some money in his possession. When he learned that a person from the tribe of Quraish who was living in Madinah, was about to set out for Yemen, he decided to hand him some money so that he could purchase for him some merchandise for trade.
When Isma`il consulted his father, Imam Sadiq (as) about the issue, the Imam (as) inquired: "Does the man consume intoxicants?"
"People say so, but how do we know they speak the truth?" replied Isma`il.
The Imam (as) advised him, "It is not in your interest to give him the money."
But Isma`il still gave his money to the person, who proceeded on his trip and in the course of it, embezzled the funds.
During the season of Hajj, both Imam Sadiq (as) and Isma`il went on pilgrimage. Isma`il was in the process of performing the Tawaf of the Ka'bah when the Imam (as) noticed that he was continually beseeching Allah to redeem his losses.
Manoeuvring himself through the crowd, the Imam (as) reached his son and placing his hand upon his shoulder, squeezed it lightly and said: "My Son! Do not seek anything from Allah needlessly, for you have no right upon Him. You should not have trusted the person in the first place. It is not upon others to rectify one's own wrongdoing."
"The people used to say that he consumed intoxicants but I had not seen him consume it!" said Isma`il.
The Imam (as) advised him further: "Consider the talks of the believers to be correct and do not trust a drunkard; be wary of giving money to those who are foolish and weak of understanding just as has been stated in the Qur'an). Who could be more foolish than a drunkard? Suggestions and intermediation of a drunkard in issues related to marriage should not be accepted nor should one place trust in his possession for he is bound to misappropriate it. A person who relies on a drunkard has no right whatsoever upon Allah that he may seek from Him compensation for damages suffered by him."
4 – Sheikh Murtadha Ansari
The late Sheikh Murtadha Ansari, in the company of his brother, travelled from Kashan to Mashhad and then arrived in Tehran where he eventually settled down in Madershah madrasah in which he shared a room with one of the students.
One day, the Sheikh gave the student some money so that he could buy some bread for both of them. When the student returned, the Sheikh noticed that he had brought some sweetmeat too, which he had placed on top of the bread. Turning to the student, he said: "From where did you get the money to purchase the sweetmeat?"
"I borrowed it," replied the student.
The Sheikh took only that portion of the bread that had no sweetmeat on it, saying: "I shall not eat the sweetmeat for I am not sure I may live long enough to repay the debt!"
Years later, when that student came to Najaf, he went to the Sheikh and asked: "Now that you are at the head of the Hawza aIlmiyyah and the Marjaa of the entire Shiaa world, tell me, what did you do that Allah granted you this great success?"
"It is because I did not have the courage to eat even that portion of the bread which lay beneath the sweetmeat, but you had the audacity to eat the bread as well as the sweetmeat!" replied the Sheikh.
5 – The Objection of Aqil
Once, after becoming the caliph, Imam Ali (as) ascended the pulpit, praised Allah and said to the assembly: "By Allah, as long as I have in my possession (even) one branch of a date-palm, I shall not extend my hand towards your wealth. I am depriving myself of this wealth and am giving it to you."
At this point Aqil, the brother of Imam (as), stood up. "By Allah! You have placed me on par with that black person from Madinah," he said.
"Sit down! There is none except you, who could have spoken out in this gathering. You do not possess any kind of superiority over that black person, save for precedence in Islam, piety and reward, and these are issues which bring about superiority in the Hereafter," Imam Ali (as) cautioned him.
 Noble Qur'an, Suratul Baqarah (2), Verse 197
 Al-Kafi, Volume 2, Page 61
 Tadhkeratul Haqaiq, Page 79
 Hikayat-ha-e-Shanidani, Volume 2, Page 74; Al-Kafi, Volume 5, Page 496
 Paighambar Wa Yaran, Volume 1, Page 47; Aayan al-Shiaa, Page 329 – 347
 Noble Qur'an, Suratul Nisa (5), Verse 5 (لاَ تُؤْتُوا السُّفَهاَءَ اَموَالَکُمُ الَّتي جَعَلَ اللهُ لَکُم قِيَاماً
 Ba Mardum In Guneh Barkhord Konim, Page 35; Biharul Anwar, Volume 4, Page 267
 Dastan-ha Wa Pand-ha, Volume 4, Page 151; Zindagi Wa Shakhsiyyat-e-Sheikh Ansari, Page 70
 Namunah-e-Maaarif, Volume 3, Page 171; Al-Wafi, Volume 3, Page 60