Tafkhim (heaviness): a fullness entering the letter's sound, filling the mouth.
Tarqeeq (lightness): a thinness so the mouth isn't filled.
Three categories:
- Always heavy: The 7 Isti'la letters — خ ص ض ط ظ غ ق ("Khuṣṣa Ḍaghṭin Qiẓ"). Strongest: the 4 Itbaq letters (ص ض ط ظ).
- Always light: All other letters except the three with two states.
- Two states (heavy or light): Alif (follows preceding letter), Lam (heavy in Lafdh Al-Jalalah by conditions), Ra (detailed rules).
Five Tafkhim Levels (strongest to weakest):
- Fathah followed by Alif — قَالَ
- Fathah without Alif — قَتَلَ
- Dammah — قُلْ
- Sukoon — يَقْطَعُ
- Kasrah — قِيلَ
Question: Why is the tafkhim of Qaf in "قَالَ" stronger than in "قِيلَ"?
Answer: Because "قَالَ" has a Qaf with fathah followed by Alif (level 1 — strongest), while "قِيلَ" has a Qaf with kasrah (level 5 — weakest)