It is narrated from the first Shia Imam, Ali (AS) who said:

O’ the believer, your merit/value is increased by your knowledge and politeness. Therefore make the effort to gain both of them. Whatever is added to your knowledge and politeness, your merit/value will be increased to that amount [1].

[1] Beharul Anwaar, Vol. 1, Page 180.

Source: en.shafaqna.com