“For it is not ye that speak, but the Spirit of your Father which speaketh in you.”
Matthew 10:20 — Greek Interlinear
Church Fathers on Matthew 10:20
To the foregoing topics of consolation, He adds another not a little one; that they should not say, How shall we be able to persuade such men as these, when they shall persecute us? He bids them be of good courage respecting their answer, saying, 'When they shall deliver you up, take no thought how or what ye shall speak.'
'How or what,' one refers to the substance, the other to the expression in words. And because both of these would be supplied by Him, there was no need for the holy preachers to be anxious about either.
When then we are brought before judges for Christ’s sake, we ought to offer only our will for Christ. But Christ who dwelleth in us speaks for Himself, and the grace of the Holy Spirit will minister in our answer.