An excerpt from the will of Ayatollah Sayed Muḥammad Saʿīd al-Ḥakīm (rah)
Our advice to the believers (may Allah bless them) – especially the educated and active ones from them – is that they should connect with the ancient Islamic corpus, from the glorious Quran and the noble Sunnah. As the books of ḥadīth of the Prophet ﷺ and his Ahlulbayt (upon them all be peace) have become easy to obtain. As it is easy to understand, due to the clarity and clearness almost always found within. Because many of the books are published in edited prints that contain the commentary for what is vague from its words and meanings.
For indeed, connecting to the Islamic corpus is important firstly:
[Due to the fact that] it has a larger impact on one’s immunity from new worldviews that would conclude in the gradual deviance of a Muslim, causing them to leave the truth without even realising this is the case.
And it has been found attributed to them (upon them all be peace): “Those who take their religion from the Book of Allah and the Sunnah of the Messenger of Allah ﷺ, the mountains will tremble before they do- and whoever takes their religion from the mouths of men, they will apostasize by [the mouths of] men.” 
So therefore the one who lives the heritage of the Prophet ﷺ and his Ahlulbayt (upon them all be peace) it is as if he has lived with them and knows their direction. And if a narration strayed from this direction it will be easy for them to interpret it or know the reasons behind its issuance because of Taqiyyah (dissimulation) or other reasons. And if one does not connect with their heritage (upon them all be peace), then the deviated will take advantage of this and the one who takes from them will be deceived by their understanding of it and will join in their deviation.
This would be the case if the deviated ones claim to be affiliated with our sect. But if they are strangers from it, the matter is more dangerous- and the need for the connection with the Islamic heritage is certainly [required]. And Allah (may He be glorified and Exalted) is the Protector and Restrainer.
And secondly: It has a greater impact on the gradual improvement of the Self and the righteous conduct of man. It [the corpus] comprises of various instructions from spiritual upbringing, apt actions, and an innate disposition through which one becomes glad and reaches confidence by, for they will feel that such things have been issued from a clear eye, a wise truthful advisor- in so that the believer responds to it and embodies it in action. And [it will be a corpus] that is sincere and compassionate, causing the individual to be concerned with [positive] reform of the people, striving to advise them.
|↑1||Al-Kāfi, vol 1, pg 7|