John Gill Commentary John 1:22

"They said therefore unto him, Who art thou? that we may give an answer to them that sent us. What sayest thou of thyself?" — John 1:22 (ASV)

Then said they to him, who are you ?
&c.] Since, as yet, he had only answered in negatives, who he was not, that he was not the Christ, nor Elias, nor that prophet; they desire he would give them a positive account who he was: that we may give answer to them that sent us ;
that their labour might not be in vain; that they might not come so far for nothing, without knowing who he was; and that they might be capable of giving an account of him to the sanhedrim: what do you say of yourself ?
they insisted on it, that he would openly, and honestly declare who he was, and what was his office and business; that from his own mouth, and not from the opinion and conjectures of others, they might represent him in a true light to those who had deputed them on this errand.