Objection: Because We Are Still Capable of Sinning, We Must Be Subject to Sickness, an Effect of Sin
This argument can be extended as follows: “Because we are still capable of sinning, we must be subject to going to hell, an effect of sin.” As you can see, this objection misses the whole point of redemption! Jesus redeemed us from the punishment for our sins! While it is possible to get sick, we are redeemed from sickness and we can run it off in the name of Jesus.
Sin definitely DOES lead to sickness, so repentance is in order if you are engaged in sin. However, Jesus did not demand that people repent of every sin they could think of before He healed them. His mercy spares us what we deserve if we turn to Him.
However, unrepentant sin can just lead to more sickness from which you’ll need to be healed. For example, homosexuals reap in their body the due punishment for their error (Romans 1:26-27). So if you receive healing but don’t repent for practicing homosexual sin, you will just end up needing healing again. Jesus warned the man whom He healed at the Pool of Bethesda to sin no more, lest a worse thing come upon him (John 5:14)! Paul warned the Corinthians to quit sinning against each other at the communion table lest they get sick and die prematurely (1 Corinthians 11:27-32). Getting healed would be of little use to someone there who was going to just keep on defrauding his brothers in Christ – the person would just get sick again and possibly just drop dead.
So we can see from the examples above that sin certainly CAN lead to more sickness! However, sin does not have to dominate a Christian (Romans 6:14). Sin still carries a price tag, but we can rule over sin and stop practicing it, and meanwhile, receive healing from Jesus for whatever mess our sin got us into.