Tanzīh: Keeping God clear of every likeness
Tanzīh is the plain admission that nothing we can name or measure holds God. Someone starting a huge work for God feels a gap open: however big the thing grows, it stays small beside the one it is meant for. Living with that gap keeps a person honest, and the work goes ahead without anyone pretending it has caught hold of God.
Being unable to understand him is itself understanding: the mind's limit is honest knowledge
Al-Ghazali often repeats this line from Abu Bakr, the Prophet's closest friend. Thinking hard about God ends with the mind out of road, and at first that feels like failing. Running out is the honest result, and admitting it puts a person nearer the truth than any confident description would.
Faqr: Poverty, having nothing of one's own
Faqr names the need that never goes away, since nothing a person holds started with them. Someone at the top of their powers can feel smallest, because the size of what they now handle shows how little of it they produced. The Quran says it flatly, that people are the poor ones and God is the rich, and admitting that comes as relief rather than shame.
My heaven and My earth do not hold Me, but the heart of My believing servant holds Me: God's place is a person
Sufis repeat these as God's own words, passed on by the Prophet. Anyone anxious that nothing they make could ever be big enough is measuring the wrong space. The room God is said to take is inside the person, and outward work matters as far as it keeps that room clear.
Ikhlāṣ: Sincerity, one aim and no other
Ikhlāṣ is the single aim the Prophet pointed to when he said actions count by their intentions. Large undertakings draw in other motives easily: reputation, legacy, the quiet pleasure of being the one who got it done. Since nothing made by hand adds anything to God, the worth of the work sits wholly in the reason behind it.