A.T. Robertson Commentary Mark 12:32

"And the scribe said unto him, Of a truth, Teacher, thou hast well said that he is one; and there is none other but he:" — Mark 12:32 (ASV)

And the scribe said (ειπεν αυτω ο γραμματευς). Mark alone gives the reply of the scribe to Jesus which is a mere repetition of what Jesus had said about the first and the second commandments with the additional allusion to 1 Samuel 15:22 about love as superior to whole burnt offerings.

Well (καλως). Not to be taken with "saidst" (ειπες) as the Revised Version has it following Wycliff. Probably καλως (well) is exclamatory. "Fine, Teacher. Of a truth (επ' αληθειας) didst thou say."