Congratulations with the statement Mabruk
Question :
What is the ruling on congratulating someone with the word Mabruk, as it is said that it is taken from the word Baruk meaning the kneeling of a camel, and it does not have the meaning of Mubarak (may you be blessed) from the word Barakah (blessing)?
Answer:
The word is fine since most people only use it to mean Barakah (blessing), then according to the custom it means the same thing as Mubarak. I also do not see that it is correct according to the rules of conjugation, to say that it is derived from Barak so I do not see any thing to prevent the usage of Mabruk to mean Mubarak.
Source:
Ibn 'Uthaimin
Fatawa Islamiyah, Vol. 8 Page 324