The Cambridge dictionary defines wisdom as using knowledge and experience to make good decisions and judgments. (1) The most similar equivalent for this word in Arabic is the word  “حکمة” (“Hikmah”) which denotes justice, knowledge and tolerance. (2) 

This word has been used so many times in the holy Quran and has a special meaning in  Islamic literature. The holy Quran says:
Allah grants wisdom to whomever He wishes, and he, who is given wisdom, is certainly given an abundant good, and none takes admonition except those who possess intellect. (2:269) 
About this verse of the Quran, Imam Sadiq (AS) says:
(In this verse) Allah The Almighty has portrayed the intellectuals in the best way. (3)

Hikmah is the message of the Prophets

Allah The Almighty has rapidly pointed out this fact that He has sent the prophets with “Hikmah” and they should teach people how to be wise. The holy Quran says:

Allah certainly favored the faithful when He raised up among them an apostle from among themselves to recite to them His signs (the verses of Quran) and to purify them and teach them the Book and wisdom, and earlier they had indeed been in manifest error. (3:164)
And:
There have already come to them, reports (via the Prophets) containing admonishment, [and representing] far-reaching wisdom; but warnings are of no avail! (4:54)
Also: 
Invite to the way of your Lord with wisdom and good advice and dispute with them in a manner which is the best manner.. (16:125)
And: 
When Jesus brought those manifest proofs, he said, ‘I have certainly brought you wisdom, and [I have come] to make clear to you some of the things that you differ about, so be wary of Allah and obey me. (43:63)

Allah almighty even says that the holy Quran is a book full of wisdom:
These are among [precepts] that your Lord has revealed to you of wisdom. (17:39)
These are the signs of the wise Book (31:2)

What is wisdom in the eyes of Allah?

The original meaning of the word “Hikmah” is wisdom, knowledge and tolerance and the ability to use your knowledge in the best way; but Allah The Almighty prefers some special kinds of wisdom. The verses of the Quran and the hadiths, try to clarify the true meaning of wisdom from Islamic sight.

Obedience towards Allah 

•    Abu-Basir, one of the brilliant pupils of Imam Sadiq (AS) once asked him about the verse; “He grants wisdom to whomever He wishes (2:269)”. Imam Sadiq (AS) replied, “That (Wisdom) is obeying Allah and knowledge about Islam” (4)
•    Imam Baqir (AS) also says that “Hikmah” means: “not to commit the sins that Allah has ordained for it the Hell as a punishment” (5)
•    Once Prophet Muhammad (PBUH & HP) asked a group of people who they are.
They said that they are some faithful people.
The Prophet (PBUH & HP) asked: “What are the signs of your faith?”
They said: “We are content about what Allah has planned for us and we are submissive to the order of our God and we trust in him for everything.”
The Prophet said: “You are so knowledgeable and wise the way that your wisdom can almost make you like prophets.” (6)

Knowing our Imams

Imam Sadiq (AS) about the verse “…and he, who is given wisdom, is certainly given an abundant good (2:269)” said ,“The abundant good is knowing Imam Ali (AS) and the other Imams (AS)” (7) 
He also said: “(The “Hikmah” mentioned in the verse is) obeying Allah and knowing the Imam (of your time)”
In Arabic, the word “جهل” (Jahl) means “Ignorance”, which can be considered the opposite of “Hikmah”. So anyone who is not “Hakim” (wise) is “Ignorant” in Islamic culture. There is a hadith narrated from the Prophet (PBUH & HP) in which he said:

Anyone who dies while they don’t have an Imam will have died like a person in the ages of ignorance (8)

This hadith has been narrated by all Muslims’ Sunnis and Shiites and the authenticity of this record is undeniable. 
About knowing the Imam, Imam Sadiq (AS) also said:
Anyone from among the followers of Prophet Muhammad (PBUH & HP) who understands the status and the rights of their Imam, will find how delightful  having faith is.(9)

Understanding Religion

The last meaning of “Hikmah” mentioned in the Hadiths is “Fiqh” (jurisprudence) which means “Understanding”. In Islamic culture, this word is  employed  to define a deep understanding of religion and profound knowledge about  it . (10)
Imam Sadiq (AS) said: 

“Hikmah is the knowledge about religion and understanding it (Fiqh). Therefore, anyone who understands the teachings of the religion is a “Hakim” (a wise person). Indeed above all, Satan wishes the ones who deeply understand religion, to be dead.” (11)
The Holy Prophet (PBUH & HP) said: 
Allah has given me the Quran and he also gave me Hikmah just like the Quran and every house which therein is no Hikmah is nothing but a ruined place. So learn Fiqh and get to know the religion so that you don’t die like ignorant people. (12)

To wrap up, in the Islamic view, “wisdom” means knowing how to live as a good servant of Allah and living the same way. As you see, all the meanings mentioned in the Quran and the Hadiths are about knowledge of religion and living the way religion indicates. Knowing your Imam (who is the leader Allah has chosen for you) is the best way to understand what you should do and how you should obey the orders of Allah.  It is then obvious that all these different meanings and teachings employ a common concept which is obeying the order of Allah after having enough knowledge about it.  
It is then obvious that all these different meanings and teachings employ a common concept; obeying the orders of Allah after gaining and enjoying competent knowledge about them.

Resources

1.  https://dictionary.cambridge.org/dictionary/english/wisdom 
2. Al-Ain, Khalil ibn Ahmad al-Farahidi, vol.3, pg.66
3. Al-Kafi, Sheikh Koleini, vol.1, pg.13
4. Tafsir noor ath-Thiqhlain, al-Huvaizi, vol.1, pg.287
5. Tafsir, Al-Ayyashi, vol.1, pg.151
6. At-Tohid, Sheikh Saduq, pg.371
7. Tafsir noor ath-Thiqhlain, al-Huvaizi, vol.1, pg.287
8.  Musnad Ahmad ibn Hanbal, vol.28, pg.88
9.  Basa’ir ad-Darajat, Muhammad ibn Hassan as-Saffar, pg.412
10.  Sihah, al-Johari, vol.6, pg.2243
11.  Tafsir, al-Ayyashi, vol.1, pg.151
12.  Majma al-Bayan, Sheikh at-Tabarsi, vol.2, pg.194
     

According to what has been said in the first part of this article, the income one earns is either Halal (gained through lawful ways), which can be freely spent, or Haram (gained through foul means), or sometimes of doubtful origins (mixed up of both Haram and Halal), which must be seriously avoided. Now you might wonder what some of the precise examples of unlawful earning are in today’s world.

What Are the Instances of Unlawful Earning in Islam (Haram Income)?

Riba (Usury)

Translated as usury, Riba refers to unfair, exploitative interests made in business. The unjust interest gained from the repayment of a loan or the simultaneous exchange of unequal commodities are the two common examples of usury. “There is the principle of the relationship between one's efforts and the amassing of wealth and the importance of participating in the risk of losing one's wealth as well as increasing it in any economic transaction. That is why Riba or interest is forbidden in Islamic Law” [1] [i].

Bribery

Prophet Muhammad (PBUH&HP) has said: “The worst unlawful earning is the income a governor gains through bribery” [2]. When some people bribe to gain what they want easily, the others who avoid giving bribes for any reason will face many difficulties to obtain what they are entitled to. Also, the bribe receivers will not fulfill what they are required to do by law unless they are bribed.

So, if bribery spreads among people, especially government officials, in a society, it will definitely lead to an increase of corruption within the community [ii].

Profiteering and Defrauding

One of the great sins in Islam is cheating in selling things, which could be of two kinds; selling something at a higher price than its real value, especially when there is a shortage of that product in the market, and also selling short measures to consumers [iii]. The loss of public trust and financial corruption are among the most devastating results of this sin.

There are also other examples for selling short measures, one of the most common of which happens in offices when employees are not conscientious enough to fulfill their job commitments and responsibilities. So, the income they earn is Haram.

Drug Dealing and the Trade of Alcoholic Drinks

Any income one gains through the role she/he has in producing, distributing, or consuming alcoholic beverages and also drug is considered Haram:

“They ask you about wine and gambling. Say, "In them is a great sin and [yet, some] benefit for people. But their sin is greater than their benefit…"” (2:219)

Muslims believe there is no harming nor reciprocating harm in Islam. So, they seriously avoid anything that inflicts harm upon them or their fellow brothers.

Gambling

Based on the verse above, the money one earns through gambling is Haram, too[iv].

That is because Islam highly recommends earning the livelihood through productive jobs and encourages hard work and striving to earn money rather than becoming wealthy or losing all one’s money overnight.

Ghina

The income one may earn by singing or playing a song which is typical of or suitable for frivolous gatherings, and carouses are also unlawful (Haram) [v].

Indecency

“Indeed those who want indecency to spread among the faithful—there is a painful punishment for them in the world and the Hereafter, and Allah knows, and you do not know” (24:19)

There are numerous instances of indecency in the world we are living today, from the provocative pictures of countless celebrities anyone can find in media, on the internet, etc. to the films that encourage immorality, and to sexual exploitation of women and so forth and so on. In fact, Islam has been sent to spread and complement the best of morality [4].

Therefore, the income earned through any attempt to spread any immorality or indecency in the society is certainly Haram.

Magic and Fortune Telling

Magic and fortune telling are believed to be destructive in the Islamic teachings, since according to the Quran: “Your omen is with Allah” (27:47), so, we should not put our trust in anyone except Him. Islam considers magic an act of devil and a great sin which has to be avoided [vi].

What has been mentioned above are among the most common examples of unlawful income. There are other instances as well which you can ask a proficient Islamic jurist or scholar about. On top of that, human’s common sense and reason can indicate what is exactly unlawful (Haram) and should be avoided.

This article is to give you some hints so that you become more cautious about your income in order to lead a decent and virtuous life.

Notes:
[i] “Those who exact usury will not stand but like one deranged by the Devil’s touch. That is because they say, ‘Trade is just like usury.’ While Allah has allowed trade and forbidden usury” (2:275).

[ii] “Do not eat up your wealth among yourselves wrongfully, nor proffer it to the judges in order to eat up a part of the people’s wealth sinfully, while you know [that it is immoral to do so]” (2:188).

[iii] “‘O my people! Observe fully the measure and the balance, with justice, and do not cheat the people of their goods, and do not act wickedly on the earth, causing corruption’” (11:85).

[iv] “O you who have faith! Indeed wine, gambling, idols, and the divining arrows are abominations of Satan’s doing, so avoid them, so that you may be felicitous” (5:90).

[v] “Among the people is he who buys diversionary talk that he may lead [people] astray from Allah’s way without any knowledge, and he takes it in derision. For such there is a humiliating punishment” (31:6).

[vi] “…and Solomon was not faithless but it was the devils who were faithless—teaching the people magic and what was sent down to the two angels at Babylon, ... They would learn that which would harm them and bring them no benefit; though they certainly knew that anyone who buys it has no share in the Hereafter. Surely, evil is that for which they sold their souls, had they known!” (2:102).

References:

1. S.Hussain Nasr, A Young Muslim’s Guide to Islam, p.58
2. al-Jame al-Saqir, vol. 2, p. 45
3. Allama al-Hilli, Nahj al-haqq wa kashf al-sidq, p. 495
4. Kanz-ol-a’maal, 13th vol. p.151, Hadith #36472