John Chrysostom

And then, when He had so said, "He charged them that they should tell no man that He was the Christ." And why did He charge them? That when the things which offend are taken out of the way, and the cross is accomplished, and the rest of His sufferings fulfilled, and when there is nothing any more to interrupt and disturb the faith of the people in Him, the right opinion concerning Him may be engraven pure and immovable in the mind of the hearers. For, in truth, His power had not yet clearly shone forth. …

Homily on the Gospel of Matthew 54 ↗

Theophylact of Ohrid

Then charged He His disciples that they should tell no man that He was the Christ. Before the Cross, Christ wanted to obscure His own glory. For if, before the Passion, men heard that He was God and then saw Him suffering, how could they not be scandalized? This is why He hid Himself from the multitude, so that after the Resurrection He might be known without causing any scandal, the Holy Spirit removing all doubt by means of the miracles performed.

Commentary on Matthew ↗

Jerome

Then he commanded his disciples not to tell anyone that he was Jesus Christ. Before sending the disciples to preach, he had ordered them to announce his coming: here he instructed them not to say that he was Jesus Christ. It seems to me that preaching Christ is one thing, and preaching Jesus Christ is another. Christ is a common name of dignity: Jesus is the proper name of the Savior. …

Commentary on Matthew ↗