Ps 40:6

40:6 you have not desired. The psalmist knows that the animal sacrifices of the Old Testament were mandated by God. But if they were offered without genuine repentance and faith, God did not want them.

you have given me an open ear. This difficult phrase may be idiomatic. The Hebrew more literally translated would be “ears you have dug for me” (see text note). This would mean that God gave the psalmist ears to hear and obey. The phrase is important because it is cited in Heb. 10:5–7. Hebrews uses the Septuagint (Greek Old Testament) translation, “a body have you prepared for me.” The meaning is the same; the “ears” are to the “body” as the part to the whole. The obedience of Jesus in the body is to offer Himself once and for all, replacing the animal sacrifices of the Old Testament.