Othello Not I I must be found My parts my title... - WAEC Literature 2018 Question

Othello:   Not I. I must be found
           My parts, my title, and my perfect soul
           Shall manifest me rightly, is it they?

Iago:      By Janus, I think so

Othello:   The servants of the Duke? And my Lieutenant?
           The goodness of the night upon you, friends
           What is the news?

       (Act 1, Scene Two, Lines 29 - 34)

By Janus is_____________