This is quite a common problem where I live if frost resistant bricks were not used. The problem is worse now as most homes are insulated and heat from inside can't dry them. Also hard cement mortars rather than lime are used, the lime joints allowed water to evaporate through them. If you are going to seal the brickwork I would use a siloxane based sealer, which is said to allow the brickwork to breathe, rather than trapping moisture.
You need to find the source of your problem first. Why is there that much moisture in the wall? Why is the moisture not leaving the wall through other means (flashing/weep holes)? Post your pictures and you might get some answers.