Final answer:
The thematic statement best supported by the given excerpt from Part III of Beowulf is that living a righteous life leads to protection and favor from God.
Step-by-step explanation:
The thematic statement best supported by the given excerpt from Part III of Beowulf is: Living a righteous life leads to protection and favor from God. The excerpt expresses the belief that a person who lives their life in accordance with God's laws and seeks refuge in Him will receive defense and protection. It does not necessarily imply that God will treat those who are not good in the same way as those who are good.
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