Commentaries:
Barnes' Notes
Troubled in spirit - See John 12:27. The reason of his trouble here was that Judas, a professed friend, was about to betray him. He doubtless foresaw the deep and dreadful sorrows of his approaching death, and was also deeply affected with the ingratitude and wickedness of a professed friend. Jesus was man as well as God, and he felt like other men. His human nature shrank from suffering, and his tender sensibilities were affected not less deeply than would be those of other men by baseness and treason.
Testified - He bore witness to the truth; openly declared what he had before intimated - that one of them would betray him.
Other Barnes' Notes entries containing John 13:21:
Matthew 26:21-24
1 Corinthians 14:14
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