I have asked on this thread for someone to find a clear promise of guaranteed healing since the day of Pentecost
There is not a guaranteed result. But there is the provision for all who believe.
Just as in salvation. You have to believe. But the matter is settled in heaven. All who pray and believe they have received will.
James 5:14-15 KJV
14. Is any sick among you? let him call for the elders of the church; and l
et them pray over him, anointing him with oil in the name of the Lord:
15.
And the prayer of faith shall save the sick, and the Lord shall raise him up; and if he have committed sins, they shall be forgiven him.
This is more than a promise. It is a statement of fact. You cannot get any stronger or more in context. Word for word. There are no exceptions and no conditions except to pray the prayer of faith. The question then is why are not all healed. There is only one answer because there is only one condition. Why is faith not present? What is preventing the faith?
In the case of the Corinthian Christians, it was a matter of lack of knowledge. They did not discern the Lord's body (bread).
In the case of Paul, it was, by his own admission, a matter of pride in his life and the inability to act on the provided "sufficient grace" the Lord had already provided.
Jesus called Peter to walk on the water, but Peter feared and doubted.
The people in Jesus' hometown doubted Jesus and so limited what the Lord could do.
Even in the OT, the people believed the evil report of the ten spies, and so they all died, save 2, in the wilderness and never went into the promised land. They all died. The two who did go in, Joshua and Caleb, did so because they had faith.
We could go on and on why people fail to receive the things God has given us.
There are cases where we do not know what was blocking or preventing faith, such as Timothy.
But never can we question or doubt the will of God. Never can we say He has not provided. If there must be blame involved, it is not God. We can only seek the reasons why we have not or cannot receive.