The Jews took up stones - Stoning was the punishment of a blasphemer, Leviticus 24:14-16. They considered him guilty of blasphemy because he made himself equal with God, John 10:33.
Again - They had before plotted against his life John 5:16, John 5:18, and once at least they had taken up stones to destroy him, John 8:59.
Other Barnes' Notes entries containing John 10:31:
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