They kept not the covenant of God, and refused to walk in his law; They kept not the covenant; of God - They abandoned his worship, both moral and ritual. Thev acted like the Ephraimites in the above case, who threw down their bows and arrows, and ran away.
Related Commentaries of Psalms 78:10
Psalms 78:10
10 They kept not the covenant of God, and refused to walk in his law;