This article starts from the point that the reception of the same song can vary considerably when sung by different singers. Public empathy depends on the content of the song and the listener's own actual experience or emotional solidarity, and the degree of empathy may vary depending on who sings the song. This can be understood by connecting it with logos, ethos, and pathos presented by Aristotle as a means of persuasion. Pathos is related to the emotions or sentiments of the audience, and ethos is related to the speaker's personality. Therefore, based on the discussion of saseolsijo(사설시조), this article aims to expand the realm of interpretation and appreciation by focusing on the on-the-spot of performance in singing. When understanding classical poetry, it is much easier to understand the song when the author's context and textual situation surrounding the author are clearly revealed. When gagok(가곡) are sung at a performance site, the expression pattern and audience appreciation attitude will vary depending on the audience and the singer. Therefore, it should be considered that the performance of private poetry was not fixed, and the extension had flexibility that could be expanded depending on the performance site.