nurse a viper in (one's) bosom
To befriend, look after, or take care of someone who proves to be traitorous, untrustworthy, deceitful, or ungrateful. I thought the profligate had seen the light and was seeking redemption, and so I took him into my care. But before long, I knew I had nursed a viper in my bosom, as I awoke one morning to find myself robbed blind! I thought our love was not only mutual but indestructible; and yet, I have nursed a viper in my bosom all these years: my darling husband has cast me out and run off with a younger woman.
nurture a viper in (one's) bosom
To befriend, look after, or take care of someone who proves to be traitorous, untrustworthy, deceitful, or ungrateful. I thought the profligate had seen the light and was seeking redemption, and so I took him into my care. But before long, I knew I had nurtured a viper in my bosom, as I awoke one morning to find myself robbed blind! I thought our love was not only mutual but indestructible; and yet, I have nurtured a viper in my bosom all these years: my darling husband has cast me out and run off with a younger woman.
nourish a viper in (one's) bosom
To befriend, look after, or take care of someone who proves to be traitorous, untrustworthy, deceitful, or ungrateful. I thought the profligate had seen the light and was seeking redemption, and so I took him into my care. But before long, I knew I had nourished a viper in my bosom, as I awoke one morning to find myself robbed blind! I thought our love was not only mutual but indestructible; and yet, I have nourished a viper in my bosom all these years: my darling husband has cast me out and run off with a younger woman.
viper in one's bosom
Also, snake in one's bosom. An ungrateful or treacherous friend, as in I got him dozens of freelance jobs, and then he told everyone I was a lousy musician-nothing like nourishing a viper in one's bosom . This metaphoric expression, often put as nourish a viper (or snake) in one's bosom, comes from Aesop's fable about a farmer who shelters a snake dying from the cold, which then fatally bites him after it recovers. It was referred to by Chaucer and Shakespeare, and appeared in numerous proverb collections.