#1— the DIVINE INSPIRATION of the Scriptures.
That as Moses spoke, God’s words, were being faithfully revealed to humanity.
Which requires…
#1—that Moses actually HEARD God speak,
#2— despite Moses being imperfect, despite his personality, his culture, his biases, God was able to work thru him…
#3—despite there being an immediate context, in which Moses lived (3400 years ago, with all kinds of cultural differences, euphemisms & customs), divine inspiration means it’s still God’s Word or Message.