How do i recover my wifi pass from android using adb?
Using this method won't work for you, since /data is not accessible except after acquiring root permissions. But if you can root your device, try this afterwards:

adb shell
su         # allow it from phone if required
cp /data/misc/wifi/wpa_supplicant.conf /sdcard/
exit
adb pull /sdcard/wpa_supplicant.conf


Sorry but AFAIK this can't be done without root.