Weren't the Ten Commandments "nailed to Jesus' cross"? If so, they don't apply to the Christian.
The OT law included temporary regulations that applied specifically to the religious and civil life of Israel, living under the Old Covenant, in the land of Canaan. It also included moral laws of a more permanent and universal nature, such as the Ten Commandments (and the commands Jesus mentions in Matt. 22:37-39). In those places where New Testament passages speak against the law, they are not denying the universal moral teachings (like the Ten Commandments), but are denying: a) that anyone can be saved by keeping the law (i.e., justification by law-keeping, rather than justification by faith), or b) that the temporary parts of the law which applied to Old Testament Israel (Heb. 8:6-13; 9:9-10; 10:1-4) remain obligatory for the New Testament Christian.
Eph. 2:15 is an example of b), above. In the context of uniting Jew and Gentile in the church (see Eph. 2:14, especially), Paul speaks of Christ, "abolishing in his flesh the law with its commandments and regulations." He doesn't mean Christ did away with the law altogether, since Christ himself denied that he came to do that (Matt. 5:17, and see also Rom. 3:31). He means that the ceremonial parts of the law which had separated Jew and Gentile (laws about "clean" and "unclean" foods, for instance--Mark 7:18-20) were now obsolete. The result is that the "hostility" between Jew and Gentile has now been put to an end, at the cross (Eph. 2:16). This passage does not speak about the Ten Commandments, which contained nothing which required the separation of Jew and Gentile.
Colossians 2:13b-14 is primarily an example of a), above. It says of God (through Christ): "He forgave us all our sins, having canceled the written code, with its regulations, that was against us, and that stood opposed to us; he took it away, nailing it to the cross." Deut. 31:26-27 describes the only way in which the Old Testament law could be characterized (by Paul) as "against us." It gives testimony to our sin and rebellion. But if forgiveness now comes through Christ ("he forgave all our sins," Col. 2:13), not by law-keeping, then the law's condemnation is forever removed. The term "written code" is the same one which meant "indictment" or "bill of indebtedness" in the New Testament. It is that indictment or indebtedness (caused by sin) that was "nailed to the cross" (in the sense that complete forgiveness came, when Christ was nailed to the cross). To say that the law cannot be used to try and earn salvation is not to say that the moral teaching of the Old Testament is suddenly declared "a dead letter" for the Christian. Paul would "turn over in his grave" (so to speak!) if he thought we were using his words to urge believers to start disobeying the Ten Commandments!
The OT law included temporary regulations that applied specifically to the religious and civil life of Israel, living under the Old Covenant, in the land of Canaan. It also included moral laws of a more permanent and universal nature, such as the Ten Commandments (and the commands Jesus mentions in Matt. 22:37-39). In those places where New Testament passages speak against the law, they are not denying the universal moral teachings (like the Ten Commandments), but are denying: a) that anyone can be saved by keeping the law (i.e., justification by law-keeping, rather than justification by faith), or b) that the temporary parts of the law which applied to Old Testament Israel (Heb. 8:6-13; 9:9-10; 10:1-4) remain obligatory for the New Testament Christian.
Eph. 2:15 is an example of b), above. In the context of uniting Jew and Gentile in the church (see Eph. 2:14, especially), Paul speaks of Christ, "abolishing in his flesh the law with its commandments and regulations." He doesn't mean Christ did away with the law altogether, since Christ himself denied that he came to do that (Matt. 5:17, and see also Rom. 3:31). He means that the ceremonial parts of the law which had separated Jew and Gentile (laws about "clean" and "unclean" foods, for instance--Mark 7:18-20) were now obsolete. The result is that the "hostility" between Jew and Gentile has now been put to an end, at the cross (Eph. 2:16). This passage does not speak about the Ten Commandments, which contained nothing which required the separation of Jew and Gentile.
Colossians 2:13b-14 is primarily an example of a), above. It says of God (through Christ): "He forgave us all our sins, having canceled the written code, with its regulations, that was against us, and that stood opposed to us; he took it away, nailing it to the cross." Deut. 31:26-27 describes the only way in which the Old Testament law could be characterized (by Paul) as "against us." It gives testimony to our sin and rebellion. But if forgiveness now comes through Christ ("he forgave all our sins," Col. 2:13), not by law-keeping, then the law's condemnation is forever removed. The term "written code" is the same one which meant "indictment" or "bill of indebtedness" in the New Testament. It is that indictment or indebtedness (caused by sin) that was "nailed to the cross" (in the sense that complete forgiveness came, when Christ was nailed to the cross). To say that the law cannot be used to try and earn salvation is not to say that the moral teaching of the Old Testament is suddenly declared "a dead letter" for the Christian. Paul would "turn over in his grave" (so to speak!) if he thought we were using his words to urge believers to start disobeying the Ten Commandments!