Diligence—carefulness and persistent effort or work—is listed as one of the seven heavenly virtues.[relevant?] It can be indicative of a work ethic, the belief that work is good in itself.
Bernard et al. define diligence in students as the effort they put towards balanced and holistic development in mental, physical, social, and spiritual dimensions. They find that it correlates with academic performance, especially with younger students, and that the support of parents and educators encourages students to be diligent. Other factors that encourage student diligence include motivation, discipline, concentration, responsibility, and devotedness.
The last words of the Buddha were, "Strive on with diligence." Diligence is an integral part of all Buddhist teaching, and considered the fourth of the pāramitā. In Mahayana tradition, diligence is the third pāramitā and the first said to lead to liberation, and it is said that its practice brings an increase of qualities.
In Christianity, diligence is the effort to do one's part while keeping faith and reliance in God. In other words, diligence and faith are two sides of a mystery. One does not know how, despite one's effort, it all works out; but diligence, when combined with faith, assures spiritual success. Diligence as one of seven virtues describes thoroughness, completeness, and persistence of an action, particularly in matters of faith.
We want each of you to show this same diligence to the very end, in order to make your hope sure. We do not want you to become lazy, but to imitate those who through faith and patience inherit what has been promised.
That man can have nothing but what he strives for; That (the fruit of) his striving will soon come in sight: Then will he be rewarded with a reward complete.— the Quran, 
Surah At-Taubah, Verse 105:
وَقُلِ اعْمَلُوا فَسَيَرَى اللَّهُ عَمَلَكُمْ وَرَسُولُهُ وَالْمُؤْمِنُونَ وَسَتُرَدُّونَ إِلَىٰ عَالِمِ الْغَيْبِ وَالشَّهَادَةِ فَيُنَبِّئُكُم بِمَا كُنتُمْ تَعْمَلُونَ
And say (unto them): Act! Allah will behold your actions, and (so will) His messenger and the believers, and ye will be brought back to the Knower of the Invisible and the Visible, and He will tell you what ye used to do.— The Quran : 9-105, 
According to Brian Hatcher, the precepts of Hinduism require a person to discover and live a dharmic life, in which they live with right intention with diligence, and with concern for the well-being of others. The Hindus celebrate Diwali, a festival of lights, where Goddess Lakshmi (also called Goddess Sri) is worshipped, who symbolizes thorough preparation, organization, diligence, and honesty. Hindus consider these characteristics essential for success and Shubh Labh (ethical profit).
Who so performeth – diligent, content – the work allotted him, whatever it be, lays hold of perfectness!— the Gita 18:45, 
Main article: Due diligence
Due diligence is the amount of diligence required to avoid negligence in professional activities. It commonly arises in major acquisitions where the legal principle of caveat emptor ("let the buyer beware") requires the purchaser to make diligent inquiries about the property or service being sold.
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