Allah (سبحانه وتعالى) says in the Qur’an,
“(This is) a Book which We have sent down to you, full of blessings, so that they may ponder over its verses, and that men of understanding may remember.” Surah Saad: verse 29.
(linguistic explanation of the word yaddabaroo is in the comments)
It is the science of tafseer which is the fruit of ‘pondering over its verses’. Tafseer comes from the root letters fa seen ra, or fassara and means to explain, to discover, elucidate, to disclose (a hidden thing), and to interpret. In Uloom al-Qur’an (the sciences of the Qur’an), tafseer is defined to be, “the science by which the Qur’an is understood, its meanings explained, and its rulings derived.” It is the crux of Uloom al-Qur’an, even though Uloom al-Qur’an comprises many other branches.
Many Muslims assume that learning the science of tafseer is not part of learning the Qur’an, when in fact tafseer is crucial to properly understanding the Qur’an itself. Without knowledge of tafseer, we can easily misunderstand the Qur’an. The science of tafseer is meant to explain to mankind the Book that has been revealed to them from Allah.
Imam as-Suyooti gives three simple reasons on why tafseer is important:
1) Allah uses the most clear, eloquent and concise language, and in doing so the meaning is clear to those who are well-grounded in the Arabic language, but not so clear to those who are not.
2) The Qur’an does not always mention the events or references for which each verse was revealed, but these must be known for the verse to be fully understood.
3) Some words may have multiple meanings, and it is the job of the person who does tafseer to explain what is meant by the word.
Many scholars of the past shed light on the importance of tafseer as well. My favorite parable was given by Iyaas ibn Mu’aawiyah who said,
“The example of a people who recite the Qur’an and do not know its explanation is like a group of people who have a written message from their king that comes to them during the night, and they do not have a lamp. Therefore, they do not know what is in the message. The example of one who knows tafseer is like a person who comes to them with a lamp and reads to them what is in the message.”
Sa’eed ibn Jubayr also said, “Whoever recites the Qur’an and does not explain it, is like an ignorant person.” Also Imam Suyooti, author of the monumental work in Uloom al-Quran al-Itqaan says,
(The science of tafseer) is the most honorable of all sciences for three reasons. The first reason is with respect to its topic. It deals with the Speech of Allah, which contains every kind of wisdom and virtue. It contains pronouncements about what has passed, reports of what will happen and judgments concerning what happens between people. Its wonders never cease. The second reason is with respect to its goal. Its goal is to lead mankind to the firm Handhold of Allah, and to the true happiness, one that does not end. The third reason is with respect to the great need for this science. Every aspect of this religion and this world, in the near or distant future, is in need of the sciences of the sharee’ah and knowledge of the religion, and this knowledge can only be obtained through the understanding of the Book of Allah.
Shaykh Yasir Qadhi, in his book An Introduction to the Sciences of the Qur’an, gives a beautiful parable on the relationship between Qur’an and tafseer. He says,
“the Qur’an is like a treasure trapped in a glass receptacle; mankind can view and benefit from this treasure, but they are in need of tafseer, for tafseer acts like the key that unlocks the treasure, so that mankind can benefit from it to the greatest possible extent.”