2:16 Αὐτὸς δὲ ὁ κύριος ἡμῶν Ἰησοῦς Χριστὸς καὶ θεὸς ὁ πατὴρ ἡμῶν, ὁ ἀγαπήσας ἡμᾶς καὶ δοὺς παράκλησιν αἰωνίαν καὶ ἐλπίδα ἀγαθὴν ἐν χάριτι, The presence of δέ indicates a new development along the discourse mainline; something new is happening. That new thing is the benediction, and the participants in the benediction need to be introduced and characterized. To achieve this, the entirety of 2:16 is used as a topical frame to reintroduce and characterize Jesus and God.