Concupiscence is the term the church uses to describe our own human disordered inclination to sin. These include disordered desires (desires that go against God’s plan for what’s best for us). Even after we regain God’s grace in confession we still have this tendency to sin again. None of us are perfect and we all fall under the weight of concupiscence but because God knows His creatures so well, he understands our nature and forgives us and gives us the chance to try again.
We all have things that tie us up and that keep us in their grip–all the things we are tempted by and that we desire in an unhealthy way can all be attributed to this weak tendency of ours which we term as our concupiscence.