It is narrated from the Prophet of Islam (PBUH) who said:

Whoever from my Ummah memorizes forty Hadiths (authentic narrations), such a person will be resurrected as Faqih and Alim on the Day of Judgment [1]. It is also narrated from Imam Sadeq (AS) who said: Any of our Shia Muslims who memorizes forty Hadiths and act upon them; Allah (SWT) will resurrect such a person as Faqih and scholar on the Day of Judgment [2]. Such a person, who acts on religious knowledge, will find the science of Fiqh in himself/herself and based on that knowledge, will be rewarded in the hereafter. Such an individual will go to heaven as a Faqih and will be able to intercede on behalf of others; because he/she will be told: Stay and intercede [3].

[1] Wasa’elul Shia, Vol. 27, Page 94.

[2] Amali, Sheikh Sadooq, Page 306.

[3] Mostadrakul Wasa’el, Vol. 17, Page 320.

Source:en.shafaqna.com