holding faith and a good conscience; which some having thrust away made a shipwreck concerning the faith;

 (a) It comes from an Old Testament background. It is Moses' charge against Israel that Jeshurun "forsook God who made him, and scoffed at the Rock of his Salvation" ( Deuteronomy 32:15). The Psalmist sings of how the good man will receive righteousness from the God of his salvation ( Psalms 24:5). It is Mary's song, "My soul magnifies the Lord, and my spirit rejoices in God my Saviour" ( Luke 1:46-47). When Paul called God Saviour, he was going back to an idea which had always been dear to Israel. 