How can one combine the pursuit of knowledge with da'wah?

Question:
It is observed that many of the righteous young men have turned to the pursuit of knowledge and left off calling to Allah, despite having the ability to do both, while another group has turned to calling to Allah and left off the pursuit of knowledge. Which of the two is better?

Answer:
Neither this nor that; it is obligatory to combine them, and one should remain a student and a caller to Allah . There is time for this and time for that, and it is possible. The student of knowledge should focus on seeking knowledge and equipping himself. Allah said to His Prophet: [Taha:114], and he is the Prophet of Allah (peace and blessings be upon him). So the student of knowledge should remain in the pursuit of knowledge; even if he is at the top, he must seek knowledge, and he must strive in reviewing and studying—studying with the scholars what is difficult for him—so that his knowledge increases. He should combine the two: the circles of knowledge, reading books, studying with his colleagues and brothers, and calling to Allah among his family, neighbors, and in his town and elsewhere. He should not devote himself solely to da'wah, nor solely to learning, but should combine them.
So, in the beginning of the pursuit, before he reaches the level of the scholars who are independent in research, his concern should be seeking knowledge, and his effort should be directed toward the pursuit of knowledge. His time should be spent on this, which is the priority, namely seeking knowledge, until his knowledge increases and he becomes qualified for da'wah, and qualified for studying and reviewing books at the start of the path. He is not yet qualified for this. So he must have knowledge of the fundamentals: the principles of jurisprudence, the terminology of hadith, and knowledge of the rulings of the Shari'ah. This is so that he becomes qualified to review the evidence, to prefer the stronger position in matters of scholarly disagreement, to refute the false, and to take the lead in calling to Allah. This is also so that he does not fall into making lawful what Allah has forbidden, or making forbidden what Allah has made lawful, due to his lack of knowledge.
So, it is necessary to focus first and foremost on the pursuit of knowledge and gaining understanding in the religion. This does not prevent him from calling to Allah according to his knowledge within his circle and surroundings. Then, when he reaches the level of the scholars, he should strive in calling to Allah , while remaining in the pursuit of knowledge, and remaining in the means of acquisition, review, study, and reading books, and clarifying the difficult issues of scholarly disagreement. However, he should be more occupied with da'wah; because he is qualified for this, and because he has acquired from knowledge what makes him one who is fit to teach, to call to Allah, and to guide people to good.