Theodoret (PG 80, 1425c) on Psalm 70:19-20 LXX (= 71:19-20 RSV): o( qeo/s, e(/ws u(yi/stwn a(\ e)poi/hsas megalei=a; o( qeo/s, ti/s o(/moio/s soi?. ("O God, even to the highest places what magnificent things you have done; O God, who is like you?"). However, the text here does not match perfectly, and requires including o( qeo/s from the second line. Perhaps Theodoret was also thinking of Luke 1.48-50 (= Odae 9.48-50 LXX): i)dou\ ga\r a)po\ tou= nu=n makariou=si/n me pa=sai ai( geneai/, o(/ti e)poi/hse/n moi megalei=a o( dunato/s ("Look, for from now on all the generations will count me blessed, because the Lord has done magnificent things for me"). This is Mary's song of praise, the "Magnificat".
See also mu 358, mu 359, mu 360.