The Standalone Heh of Haazinu — Deuteronomy 32:6
הַ לְיהוָה תִּגְמְלוּ־זֹאת
What to look for
The heh opening the rebuke is enlarged — and in the Leningrad Codex it is even written standing apart from the rest of its word.
What it is
An enlarged letter opening the Song of Moses' accusation against a forgetful people.
Why it matters
The question mark of the whole song hangs on this one letter: the heh is the Hebrew question-prefix, and here it towers, as if the question is bigger than the sentence.
How it has been understood
Heh is also the letter tradition associates with God's own name and breath. Written large and alone before 'to YHVH,' it reads almost as a gasp — the song catching its breath before asking how the people could repay their Father this way.