Taqlīd: Belief taken secondhand
Al-Ghazali used this word for belief someone holds only because the people around them held it. A person can spend years inside a religion, doing everything correctly, and never look into it themselves. The whole thing rests on other people's certainty, so under pressure they find they were carrying a habit rather than a conviction.
I seek refuge in You from knowledge that gives no benefit: learning that changes nothing
The Prophet prayed to be spared this. Someone can know exactly what is asked of them and live nowhere near it, until the knowing becomes furniture in the mind. The knowing gets repeated to other people and touches nothing in their own day, so it guards them from nothing.
'Ulamā' al-dunyā: Scholars of this world
Al-Ghazali's name for people whose learning has turned toward what it can get them: standing, income, the respect of a room. The turn is rarely a decision. Someone keeps saying the same correct things while the reason for saying them slides, until the position remains and the point of it has drained away.
Rayn: Rust on the heart
The Quran describes a film that builds on the heart from what a person keeps doing. Each time someone waves off something they know is right, they lose a little of the sight that showed it to them. After enough of that, nothing looks clear, and they believe in good faith that nothing was there.
Ghafla: Heedlessness
Sufis use this word for living as though God were absent, which nobody sits down and decides. Attention drifts toward whatever is loud and near, practice thins, and one day a person cannot say when they last thought about any of it. Nothing got argued away; it simply stopped being consulted.
Remember Me, and I will remember you: attention is answered in kind
God says this in the Quran, and Sufis build their whole practice on it. Turning toward God is met by being turned toward, and the reverse holds, so a life that leaves God out begins to feel unattended. The absence someone feels matches the distance they kept, and it lifts when their attention returns.