It is important to learn more about tawheed. Because the Prophet Sallallahu ‘alaihi Wasallam says:
مَن مات وهو يعلمُ أن لا إله إلا اللهُ دخل الجنةَ
“Whoever dies in a state of knowledge that there is no worship except Allah, he enters heaven” [Muslim:26].
In this hadith, the Prophet Shallallahu’alaihi Wasallam says يعلمُ means: “having knowledge”. So it is not just saying “laa ilaaha illallah“, but it is obligatory to know what it means, what are the conditions, what are the principles, what are the consequences, what is the cancellation and all about it.
Al Hasan Al Basri (d. 728), he was asked: “the people say that those who say Laa ilaaha illallah will surely go to heaven?”. Al Hasan says:
من قال « لا إله إلا الله » فأدَّى حقها وفرضها دخل الجنة
“Whoever utters Laa ilaaha illallah, then fulfills his rights and obligations, will surely enter heaven” (narrated by Al Asbahani in book of Al Hujjah fi Bayanil Mahajjah [2:152]).
Al Hasan once said to Al Farazdaq, when he buried his wife:
ما أعددتَ لهذا اليوم ؟ قال : شهادة أن لا إله إلا الله منذ سبعين سنة، فقال الحسن : “نعم العدة لكن لـِ « لا إله إلا الله » شروطاً ؛ فإياك وقذف المحصنات
“What are you preparing for today (the day of your death)? Al Farazdaq said: the creed of Laa ilaaha illallah since 70 years ago. Then Al Hasan said: yes right, that’s the provision. But Laa ilaaha illallah has conditions. And you should stay away from actions that accuse adultery of good women “[Majmu ‘Rasail Ibn Rajab, 3:47].
So, it is important to learn more and deeply about tawheed. Everything about it. May Allah guides us to learn tawheed and gives us the understanding of tauhid.