The words rested, wrested sound the same but have different meanings and spellings. Why do rested, wrested sound the same even though they are completely different words?
The answer is simple: rested, wrested are homophones of the English language.
recovered
Simple past tense and past participle of <xref>rest</xref>.
not tired; refreshed as by sleeping or relaxing
Simple past tense and past participle of <xref>wrest</xref>.
Definitions from Wiktionary, Creative Commons Attribution/Share-Alike License., from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved. and Wordnik.
Homophones (literally "same sound") are usually defined as words that share the same pronunciation, regardless of how they are spelled.
If they are spelled the same then they are also homographs (and homonyms); if they are spelled differently then they are also heterographs (literally "different writing").