Q.The individual is asking, can you name yourself inayyahtullaah?
A.The shaykh mentioned the origin with regards to names is that names are permissible except that which you have a prohibition for or that which you have some sort of shirk in. These types of names; inayyatullaah, baytullaah. These names are permissible as they do not have anything which is impermissible in them nor do they have shirk. However, the best of names are those that begin with Abd (servant), for example, Abdullaah, Abdur Rahmaan, Abdul Kareem or Abdul Lateef. These are the best of names, the names that begin with Abd.
Shaykh Saalih Muhammad al-Luhaydaan (May Allaah preserve him) (Kitaab-ut-Tawheed Class Q&A Session 02.02.13 Riyadh).