And those who guard their private parts.
And they maintain their chastity.
who guard their privates
And who restrain their sexual passions -
And those who to their genital parts between their legs they are protecting/guarding
The believers are those who do not engage in immoral sexual activities
And who guard their private organs
And who guard their chastity
And who guard their private parts (all the time)
And who guard their private parts
And those who guard their chastity (i.e. private parts, from illegal sexual acts