The creation of music has originated from the burst of inspiration of the composer. Many studies suggested that improvisation plays a more vital role than composition in the emergence of new forms of music. The production of music, especially in Western cultures, tends to follow its traditional music theory. With the emergence of Pythagorean music theory, Western musicology has been defined and developed in depth. The composer’s creation is based on music creation within the framework of the Western music theory. However, in recent years, with the rise of the topic of music gestures, some scholars have learned that music ontology as a four-dimensional hypercube is inseparable from the performer’s gesture. Therefore, some musicians also attempt to create flexible music from the perspective of music performers and based on performance gestures. This kind of music creation breaks the traditional music theory system and has more personal style characteristics, but few people can understand the thinking logic behind this kind of creative behavior. Therefore, this article focuses on the singing gesture and reversely analyzes its impact on musical creation. We use a recent mathematic definition of gestures and we discuss emotion from its etymological origin (from the Latin e-movere) as a gestural movement from inside out. This article conducts an in-depth analysis based on the singer’s gesture for the following two reasons: First, the literature on the connection between singing gesture theory and composition theory remains scarce. Second, gestures produced by a singer are the only performance form that is not enabled by other instruments.