Therefore 'You shall fear your God' because God sees that which is hidden. Furthermore, it will caution us with regard to being a person who curses the deaf and who causes a blind person to stumble because they do not fear them because they do not know or understand. It wasn't necessary to say 'with regard to the hearing' for they would be embarrassed and would be very angry at them. According to the peshat, one is warned with regard to cursing the deaf, for even though he will not be able to hear or get angry because of your cursing him, the Torah cautions with regard to him. with regard to the unfortunate ones of the nation, 'the deaf' serves as the categorical title (binyan av) toward/including all the rest of the nation, for it is from 'the top'/'the beginning' to 'the bottom'/'the end' that all are included in the caution. The midrash in the Gemara (Sanhedrin 66a) says that the verse (Exodus 22:27) is to caution us about those of high honor/status among the people. From where does one expand it to mean 'all people'? We learn it from the verse (Exodus 22:27) ' your people, do not insult'. 'Do not curse a deaf person'- It appears to me that this means 'a deaf person'.

Doing It Right by Bronwen Pardes