innocent as a lamb

I dont mean morally innocent: everybody who reads your articles knows youre as innocent as a lamb.

From Fanny's First Play by Bernard Shaw

But I will say for William that he was as innocent as a lamb of any carnal intentions in these improvements.

From A Circuit Rider's Wife by Corra Harris

I didn't know what had startled her, and she did not know that I had any connection with it, for I stood looking on as innocent as a lamb, with my thumb in my mouth.

From The Little Colonel's House Party by Annie F. (Annie Fellows) Johnston

And say," went on Frank, "I put a chair in back for ma, and rode along the avenue as innocent as a lamb.

From The Girl Scout Pioneers or Winning the First B. C. by Lilian Garis

There was a little laugh at this, which made the owner of the latter name turn sharply and fiercely upon the nearest boy, who shut his mouth instantly and looked as innocent as a lamb.

From Glyn Severn's Schooldays by Charles Pears