1 sn Paul uses a typical rabbinic formula here in which the OT scriptures are figuratively portrayed as speaking to Pharaoh. What he means is that the scripture he cites refers (or can be applied) to Pharaoh.
2 sn A quotation from Exod 9:16.
3 tn Grk “in the believing” or “as [you] believe,” with the object “him” supplied from the context. The referent could be God (15:13a) or Christ (15:12).