Luke 10:30-37
30 Then Jesus answered and said: "A certain man went down from Jerusalem to Jericho, and fell among thieves, who stripped him of his clothing, wounded him, and departed, leaving him half dead. 31 Now by chance a certain priest came down that road. And when he saw him, he passed by on the other side. 32 Likewise a Levite, when he arrived at the place, came and looked, and passed by on the other side. 33 But a certain Samaritan, as he journeyed, came where he was. And when he saw him, he had compassion. 34 So he went to him and bandaged his wounds,
pouring on oil and wine; and he set him on his own animal, brought him to an inn, and took care of him. 35 On the next day, when he departed, he took out two denarii, gave them to the innkeeper, and said to him, 'Take care of him; and whatever more you spend, when I come again, I will repay you.' 36 So which of these three do you think was neighbor to him who fell among the thieves?" 37 And he said, "He who showed mercy on him." Then Jesus said to him, "
Go and do likewise."
NKJV
Notice that Jesus does not say the Samaritan was in error by anointing this fellow with oil.
It is my understanding (though I could be wrong) that the staples of medical treatment in these times revolved around anointing with oil and the use of alcohol. We still do these things today. When we are wounded we first clean the wound with antiseptic (alcohol then) and then cover the wound in someway (oil then) to prevent infection.
If this is correct then the passage in James is saying to first use whatever medical treatment is available and then to have the elders pray over you and lay on hands.
Sort of like the oil was the equivalent of the church's first aid kit.
I've never researched it myself though, it is just something I heard in a sermon one time.
Asaph