Matthew Poole and continuators on Luke 17:14

14 And when he saw them; he said unto them, Go shew your selves unto the priests. And it came to pass, that as they went, they were cleansed.

It was according to the Divine Law, Levit. 14.2. That the Leper in the Day of his cleansing, should be brought unto the Priest, who was to judge whether he was healed yea or no, and to offer the offering there prescribed. Christ sends him to the Priest, partly that he might observe the Law which his Father had given in the case, partly that he might have a testimony of this his Miraculous Operation. We shall observe that our Saviour cured some being at distance from them, some by the Word of his Power only, tho he were present in the same place, others by touching of them; he certainly chose thus to vary his circumstances, in actions of this Nature, to let People know that the healing vertue was inherent in him, and that the proceeding of it from him, was not tyed to any ceremony used at the doing of the Work, which he used or omitted according to his pleasure.

Marginal references: Levit. 13.2.