steel one's heart against
Also, harden one's heart. Suppress one's feelings for, as in He finally steeled his heart against them and refused the loan, or You'll just have to harden your heart and tell them the truth. This metaphoric idiom transfers making something hard to rendering oneself insensible or unfeeling. Versions of it date from the late 1500s. Also see heart of stone.
Words nearby steel one's heart against
steel gray,
steel grey,
steel guitar,
steel lumber,
steel mill,
steel one's heart against,
steel pan,
steel trap,
steel wool,
steel-faced,
steele