eat out of (one's) hand
To be completely accepting of whatever one says or requires. You can tell the candidate has his followers eating out of his hand—they'll believe anything he says, no matter how plainly false.
eat out of someone's hand
Be manipulated or dominated by another, be submissive, as in He had the press eating out of his hand. This metaphoric expression alludes to a tame animal eating out of one's hand. [Early 1900s]
eat out of someone's hand, to
To be quite submissive. This expression, referring to a tame animal eating from a person’s hand, dates from the early twentieth century. “He’s like that,” wrote Joseph Conrad (Victory, 1915), “sometimes that familiar you might think he would eat out of your hand.”