Timothy A. Brookins, First and Second Thessalonians, Paideia Commentaries on the New Testament (Grand Rapids, MI: Baker Academic, 2021), 83:
Paul’s reference [in 1 Thessalonians 4:2] to his previous instructions (parangeliai) should be understood in connection with the philosophical concept of “precepts” – another possible rendering of the word…. Thus, whereas chapters 1-3 offered exhortation primarily by presenting Paul as a paradigm or “example” (exemplum), chapters 4-5 offer exhortation in the form of “precepts” (praecepta). The pairing of exempla and praecepta as complementary means of instruction was common in philosophical literature of the day (Seneca, Ep. 6.6; cf. Quintilian, Inst. 12.2.30). While Seneca believed that exempla were more effective than praecepta – since examples embodied doctrines in concrete form (see 1:6-8) – he also emphasized that praecepta were necessary and could function similarly (Seneca, Ep. 94.40; cf. Epictetus Diatr. 4.1.169). In distinction from doctrinae, or the general principles of a particular philosophical system (“doctrines”), praecepta constituted concrete applications of those doctrinal principles (Seneca, Ep. 94.31; 95.12). Though some Stoic philosophers rejected the need for praecepta on the premise that doctrinae were sufficient to set one thinking correctly and therefore behaving correction…others insisted that praecepta were valuable and indeed necessary (Seneca, Ep. 94.18-44; 95.34, 59-60), for praecepta divided the general principles of philosophy, or doctrinae, into specific applications, each pertinent to specific areas of obligation in the real world (Seneca, Ep. 94.21; 95.12). In the same way, Paul has introduced the general principle that Christians should live in a way that is “pleasing to God.”