In Fairy Tail (2014) episode 70, Jellal was wearing a blindfold and was being guided by Meredy. What is the reason that he was wearing this?
So Jellal blinded himself remembering how Erza was easily able to beat midnight's illusions before because of her artificial eye. There for he doesn't have that handy cap that could very well have saved him he injured his eyes making him blind along with his other severe injuries from his fight with Midnight and the rest of the Oracion Seis. If you want my honest opinion Meredy did the right thing by helping him as at the time he was hurt and couldn't see. Also to her surprise the Oracion Seis helped protect Jellal from Rusty Rose and later he regained his eye sight as he removed the blindfold.