What are the reasons for the differing opinions among scholars regarding the ruling on one who seeks nearness to Allah by adopting means that the Lawgiver has not designated as means, such as touching the Black Stone or graves, while claiming that he knows they do not inherently benefit or harm, but rather he does so to draw closer to Allah?

Devoting acts of worship to other than Allah is major shirk. As for taking means that the Legislator (Allah) has not designated as means, there is a detailed explanation: if one believes that these means are effective in themselves, then it is major shirk in Tawhid al-Rububiyyah (Oneness of Lordship). If one believes that they are merely a means and not effective in themselves, then it is minor shirk. Imam Muhammad ibn Abd al-Wahhab and Shaykh Ibn Baz agree that drawing near to other than Allah through any act of worship is major shirk that expels one from the fold of Islam. They both see a detailed explanation in the issue of excuse by ignorance, though they may differ in its application to some specific cases. Scholars are in agreement on the principle of excuse by ignorance, with variations in how it is applied and the specific issues for which one is excused. Not declaring a specific individual to be a kafir (disbeliever) does not prevent describing the act itself as shirk or kufr (disbelief).