Is it Obligatory to Learn the Arabic Language?

Learning the Arabic language is something that is obligatory without any doubt, because of the fundamental principle that is established by the ulama: "When the obligation can't be achieved except by a certain thing, then this thing is obligatory." It is not possible for students of knowledge to understand the Quran and the sunnah except by means of the Arabic language. As for speaking in it, this is recommended especially because it helps the speaker to increase in knowledge and become proficient in understanding it. Therefore, learning Arabic is obligatory. As for speaking in it, it is recommended because of the lack of evidence indicating that it's obligatory.