The main part is made up of heroic-philosophical odes, characterized by sublime wording rich in color and contrast, and pastorals with a simpler verse texture, in which there are motifs and forms of Estonian folk songs; the influence of ancient literature (Theokritos) and pre-romantics (Friedrich Gottlieb Klopstock) is also evident.

One of Peterson's projects was fulfilled in his lifetime, the German version of Kristfrid Ganander's Mythologia Fennica, a dictionary of Finnish mythological words and names (the Swedish language original was published in 1789).

Peterson's translation of Ganander's dictionary found many readers in Estonia and abroad, becoming an important source of national ideology and inspiration for early Estonian literature.

Being exceptionally talented in linguistic subjects, he quickly obtained knowledge of several languages, both ancient and modern, wrote philological treatises and made an attempt to compose a Swedish grammar.

In modern days, Peterson's linguistic manuscripts, together with the original versions of his poems and diary, were published in 2001 in an Estonian-German bilingual edition, which included some new translations.