Albert Barnes Commentary Mark 7:33

"And he took him aside from the multitude privately, and put his fingers into his ears, and he spat, and touched his tongue;" — Mark 7:33 (ASV)

And he took him aside from the multitude. Why this was done we have no means of information. It might have been to conceal from the multitude everything concerning the manner of cure, so that none might attempt to cure in a similar way.

And put his fingers into his ears, etc. Why this was done it has been found exceedingly difficult to explain. Our Lord had power at once to open his ears and loose his tongue, but for some reason he chose to accompany it with a sign. It was intended, probably, simply as a sign that the power of healing came from Jesus; to satisfy the man by the touch that he had this power, and that it could come from no other source. Our Saviour often used signs in this way to denote his power to heal. See Mark 8:23; John 9:6.