amanfang and pianowelsh described their personal walk with their father and God - and the element of trust that builds up when one's faith is practiced. just like practicing the piano - you learn to pray. and yes, rimv2, i do pray and believe that God will work things out in my life and in others lives. i pray for healing for others and believe that God will listen. i have prayed for healing in my own life and KNOW that God healed me. therefore, i believe He can heal.
proof is not the only thing. perseverance in trials is also a form of proving one's faith. joseph was innocent and in prison for 7 years for a crime he did not commit. but, during this time he did not stop praying. instead, he increased it. so much so - that he was continually elevated to higher positions and looking after the prison and then - suddenly to the second under pharoah again for being able to discern one of pharoah's dreams. he would not have had the ability to do this if he had lost the Spirit of God - or keeping in touch with the very power and mind of God to discern what to do at what time and when.
God's power is awesome. if you see it in motion in creation , that is evidence enough. but we have the calendar which allows us to also see history - and history is divided into two sections. BC and AD - before and after the death of our Savior. that is enough for me to say that i believe he impacted this earth by his presence so much - that people down thru the ages have been willing to die for the christian belief. why die? well, they believe (as all saints have) that death is merely a benchmark to another place in our eternal life. that God has promised eternal life to those who follow His words (and read them to know what they say). even if you have a mustard seed of faith and only read the 10 commandments (maybe buying a plaque) you have enough faith to move mountains. (big problems in your life). why? because problems come often from disobeying our conscience and later from the guidance of the Holy Spirit. if you go against the laws of God which are like the laws of gravity - it proves there is a higher being because you are not blessed.
i dare anyone to prove God by doing what he says and then seeing if they are blessed. over a period of 10 years. sometimes 1-2 days. it just depends on your level of perseverance and faith. no matter if you have wealth already - or are dirt poor. you can always be blessed by God. it might be the ability to be at peace mentally. or, to be able to see needs and meet them for others. there are many blessings that are unseen - but greatly cathartic to the human soul.