Parashas Vaeira · Passuk 6:2
Chabad.org — English translation + Rashi
Torah Temimah points to Yerushalmi Berachos 2:6 (verified).
English: Rabbi Shmuel bar Nachmani said in the name of Rabbi Yonatan: wherever Scripture uses the language of “speech” (dibbur), there is a particular textual innovation or special point being conveyed.
On the daf / in context: See the cited source for the full section.
Linguistic exegesis of the Torah’s use of “dibbur”
Chazal treat the opening “וידבר אלהים” as deliberately significant rather than ordinary narrative wording.