We carry this new life "in earthen vessels" (2 Cor 4:7). We are in "an earthly tent" subject to suffering, illness and death, this new life can be weakened and even lost by sin.
Through the sacraments of Reconciliation and Anointing of the Sick, Christ, who forgave the sins of the paralytic (and then healed him) wants his work of healing and salvation to continue.
“I am love and Mercy Itself. There is no misery that could be a match for My mercy, neither will misery exhaust it, because as it is being granted – it increases. The soul that trusts in My mercy is most fortunate, because I Myself take care of it.” Jesus to St. Faustina
“He did not you would not be troubled, you would not be tempted, you would not be distressed. But He did say you would not be overcome.” St. Jose Maria Escriva