Praise be to Allah.
Shaykh Muhammad ibn Saalih al-‘Uthaymeen (may Allaah have mercy on him) was asked this question and he answered as follows:
Undoubtedly calling people to Allaah is something which has a high status and is very important, because this is the mission of the Messengers (may the blessings and peace of Allaah be upon them). Allaah says (interpretation of the meaning):
“And who is better in speech than he who [says: ‘My Lord is Allaah (believes in His Oneness),’ and then stands firm (acts upon His Order), and] invites (men) to Allaah’s (Islamic Monotheism), and does righteous deeds, and says: ‘I am one of the Muslims’”
Allaah commanded His Prophet Muhammad (peace and blessings of Allaah be upon him) to say (interpretation of the meaning):
“This is my way; I invite unto Allaah (i.e. to the Oneness of Allaah — Islamic Monotheism) with sure knowledge, I and whosoever follows me (also must invite others to Allaah, i.e. to the Oneness of Allaah — Islamic Monotheism with sure knowledge)”[Yoosuf 12:108]
Of course it is not possible to call people to Allaah without any knowledge, as Allaah says here, “with sure knowledge”. How can a person call others to something of which he has no knowledge? Whoever calls people to Allaah without knowledge is saying things about Allaah which he does not know. Knowledge is the first step towards da’wah.
But it is possible to combine knowledge and da’wah from beginning to end. If you cannot combine them, then you should start with (seeking) knowledge, because that is the basis on which da’wah rests. Al-Bukhaari (may Allaah have mercy on him) said in his Saheeh, in the tenth chapter of Kitaab al-‘Ilm (the Book of Knowledge), Baab al-‘Ilm qabla al-Qawl wa’l-‘Aml (Chapter on (acquiring) knowledge before speaking or acting). He quoted as evidence for that the aayah in which Allaah says (interpretation of the meaning):
“So know (O Muhammad) that Laa ilaaha illallaah (none has the right to be worshipped but Allaah), and ask forgiveness for your sin, and also for (the sin of) believing men and believing women. And Allaah knows well your moving about, and your place of rest (in your homes)”[Muhammad 47:19]
He said: so start with knowledge.
Whoever thinks that he cannot combine (seeking) knowledge and da’wah is mistaken, because a person can be learning and can also call his family, neighbours and the people in his town to Allaah whilst he is still learning.
People nowadays are in need – indeed it is essential – of deeply rooted knowledge that will be established in their hearts, based on the sources of sharee’ah. With regard to the superficial knowledge by which a person knows just a little about the issues that he comes across, as the common people know, without any knowledge of its principles or what it is based upon, this is very limited knowledge which does not enable a person to defend the truth at a time of necessity in the face of the arguments posed by those who propagate falsehood.
What I advise the Muslim youth to do is to concentrate their efforts on seeking knowledge whilst also calling people to Allaah as much as they can and in a manner that will not prevent them from seeking knowledge, because seeking knowledge is jihad for the sake of Allaah. Hence the scholars said that if a person who is able to earn a living is kept from doing so by his pursuit of knowledge, he should be given zakaah, because that is a kind of jihad for the sake of Allaah, unlike one who does not work in order to concentrate on worship, who should not be given zakaah because he is able to work.