Judges 16:22 Midrash

וַיָּ֧חֶל שְׂעַר־רֹאשׁ֛וֹ לְצַמֵּ֖חַ כַּאֲשֶׁ֥ר גֻּלָּֽח׃ (פ)

Howbeit the hair of his head began to grow again after he was shaven.

Read midrashic interpretation of Judges 16:22: and classical rabbinic exegesis.