My take:
His speech writer ( or the person who helps him with his crib notes if Donald “writes his own speeches”) decided that Donald needed a verse referencing liberty while speaking at Liberty University. Note writer prints out 2 Corinthians 3:17 and Trump reads it exactly as written.
It’s just political pandering. No one should be shocked by it.
It’s the university’s school verse. That’s why he referenced it. Albeit awkwardly.