The 'loins' are at the center of the body and one of the primary sources of strength. When you gird your loins with a belt, it supports your body strongly. You can then maintain stability doing all kinds of work. In faith, 'girding our loins with truth' is very important. Jesus Christ is the Truth. So we should stand firmly in Jesus Christ. If we firmly stand on the truth, we will not be shaken by the attacks of the enemy devil and Satan. We will be able to overcome them no matter what they maybe. "Stand firm therefore, having girded your loins with truth..." (Ephesians 6:14).