Bitter tears. We know them. They are the tears of pain mixed with the full awareness of our own sin. They are the ones that gush from our eyes and bear pain in their saltwater mix as we taste it, sobbing uncontrollably.
Perhaps these tears of repentance and acknowledgment are so that our eyes may be washed so that we can see truly, so that our blindness is taken away (cf. John 9:1-41). Perhaps these tear-filled eyes are the most appropriate eyes for gazing upon the Holy Cross of Christ our God.