Jesus promised us that if we drink any deadly thing it shall not harm them (Christians). As we know, Christians are vulnerable to substances that can make us sick or even kill us. But "ye have not because ye ask not" in terms of this promise! You have to do something to activate the promise.
At Christian Healing Ministries, we have prayed for medicines with bad side effects to do no harm but only what it is supposed to do. Our clients would routinely receive chemotherapy and not get sick!
Since God's promise is true, why not pray for carcinogens already in our bodies? Just rebuke them. Jesus often rebuked illnesses. I have been doing that for my congregation. The number of prayer cards for healing of cancer have gone down. There is still a need for rebuking of cancerous and pre-cancerous cells, but if that's all you do, "ye have not because ye ask not" -- the cancer can come back....
How about the autism "epidemic"? It has a high correlation with getting shots with mercury and aluminum in them. I haven't had the opportunity to try this out, but we should be able to neutralize poisonous metals and ask for them to be safely flushed from the body. If the metals are the problem, the autism should reverse. No harm trying...
How about autoimmune diseases? These are caused by excess antibodies in our bodies due to unnecessary shots. Just praying for healing while the antibodies are attacking is a lost cause. Stop the attack by neutralizing the rogue antibodies before trying to bring healing.
Transplant organs add a twist to this. The chemicals the transplant
patients are given suppress the immune system and therefore could be considered
a poison. Neutralizing these medicines could kill the transplant
organ! You need to bless those medicines to do only what the doctors
intended and have no other effect. Remember this when you are praying for
a group of people you don't know.