One common mistake we make is applying to ourselves promises that are not really there from God or those that are not meant for us. We think we can look for promises all over the Bible and claim what we find. But we mustn't forget the fact that there is no one as creative as our God and diversity is a hallmark of His character. No two trees or flowers He makes are the same. When it comes to man, we are all so unique – in our body, mind, experience and capabilities. What God does with each one of us is also unique. He causes us to be born with a particular DNA, go through particular sets of training through experience and at the end there are no two of us exactly the same.
The work He wants us to do is also different for each of us. He specially chooses for us the ministry He wants us to have (1Co.12:11) and even gives each one the special emphasis that comes out from our particular make-up. No two teachers or no two pastors are the same. No two people can agree on all the doctrines because it is not just about the way we interpret the scriptures but also the particular shape of our mind into which interpretations go, based on our background and experiences!
How God deals with each one is also unique. In a general way we can say that what He has done for others He is able to do for us. But what He will actually do for us will be unique for us. God may heal someone miraculously, ask someone else to go to the hospital for treatment and even take someone to be with Him without healing here. When Mark says how believers in Jesus will experience miracles (Mk.16:17,18) it is not that all of us will experience all of those every time in our life. These things will happen among the people of God, but we cannot take it that we can 'claim' all of these for ourselves. You may have heard of those who have (actually) tested God by handling poisonous snakes based on these verses, and died (Mt.4:6,7). When Jesus sent out the disciples to go and "Heal the sick, raise the dead, cleanse the lepers, cast out demons" (Mt.10:8), they were given a special authority as apostles to do all of these and more. But what happens now is someone may cast out demons, someone else heal the sick and someone raise the dead, but this is not something all of us can 'claim' as rights or promises given by God to everyone.
When we don't understand this, people are taught to expect miraculous things saying that God did that for someone else. When that doesn't happen many are disappointed and some even fall away from the faith.
But then, what can we look forward to when we pray in faith for miracles? We believe that God is quite capable of doing any miracle He chooses, but we choose to submit to God's will in each particular case. We can ask Him to do a miracle for us but we will not insist that He has do it for us because He did it for someone else. Which do you think is the higher faith – demanding from God or submitting to God (Da.3:17,18).