E.g. Instr. in Ps., § 15 = Origen in Eusebius, H.E. vi. 25 (Philocalia 3), Hilary on Ps. 51, §§ 3, 7 = Origen xii. 353, 354, and very often on Ps. 118 (119), e.g. the Introduction = Or. xiii. 67 f., Aleph, § 12 = ib. 70, Beth, § 6 = ib. 71, Caph, §§ 4, 9 = ib. 82, 83, &c.