Christ Died For You

Well, the answer is yes and no, depending on the audience and/or depending on the antecedent of "our." If "our" means "those of me and my company" or "those of us believers," then it carries no implications regarding Christ's atonement or lack thereof on behalf of the audience. If "our" includes the sins of the audience, then it is still an appropriate thing to say to an audience of believers. The only situation in which this would not be appropriate would be one in which "our" was intended to include the sins of the audience, and was proclaimed to unbelievers.

My take on 1 Corinthians 15:3 is that Paul meant to include his own sins, those of his company, and those of his audience in his use of the word "our." Nevertheless, 1 Corinthians 15:3 is not a gospel presentation to unbelievers but a gospel presentation to believers. Believers need to hear the gospel regularly for a variety of reasons, including being corrected of error and strengthened in faith, both of which Paul was doing for the Corinthians. So, when Paul wrote that Christ died for "our" sins, he wrote from the perspective of believers to an audience that he treated as consisting of believers ("the gospel . . . which you have received and on which you have taken your stand," 1 Cor. 15:1). In the context of a believing audience (e.g., in church), his words are perfectly appropriate. Moreover, Paul was not quoting words that he had earlier spoken to the Corinthians before they had come to faith, but Paul simply reminding them of the content of their belief.