What were disgrace and spitting intended to accomplish?
Isaiah 50:6 (ESV)
6I gave my back to those who strike, and my cheeks to those who pull out the beard; I hid not my face from disgrace and spitting.
These too are mocking gestures, meant to humiliate. Disgrace was probably verbal insults and taunts. Spitting in the face was a most degrading of gestures (see Deuteronomy 25:9; Job 30:10).
6 I gave my back to those who strike, and my cheeks to those who pull out the beard; I hid not my face from disgrace and spitting.