I know that the bible say that we should believe in the lord Jesus but I need someone to help me understand more about the original meaning of the word believe so I can fully believe in a proper way.
To start, it is instructive to understand that the words "faith", "trust" and "believe" in English translations all come from the same Greek root (pisteuo).
Charles Spurgeon describes it well in his book, All of Grace:
What is faith? It is made up of three things—knowledge, belief, and trust.
Knowledge comes first. "How shall they believe in him of whom they have not heard? I want to be informed of a fact before I can possibly believe it..."
The mind goes on to believe that these things are true. The soul believes that God is, and that He hears the cries of sincere hearts; that the gospel is from God; that justification by faith is the grand truth which God hath revealed in these last days by His Spirit more clearly than before. Then the heart believes that Jesus is verily and in truth our God and Saviour, the Redeemer of men, the Prophet, Priest, and King of His people. All this is accepted as sure truth, not to be called in question...
So far you have made an advance toward faith; only one more ingredient is needed to complete it, which is trust. Commit yourself to the merciful God; rest your hope on the gracious gospel; trust your soul on the dying and living Saviour; wash away your sins in the atoning blood; accept His perfect righteousness, and all is well. Trust is the lifeblood of faith; there is no saving faith without it.
He later summarizes it this way:
Faith is believing that Christ is what He is said to be, and that He will do what He has promised to do, and then to expect this of Him.
In reality, the Greek word is not anything mysterious. However, it does not mean intellectual assent, as the demons believe there is a God--and tremble in fear as a result.
So, the definition comes from understanding the Gospel--what is to be believed and why.
Faith, believing, trusting all these are akin to one another.
Hebrews 11 says: Now faith is the substance of things hoped for, the evidence of things not seen.
Faith is a tangible force; faith is the substance of our hopes and is the evidence of unseen realities. Faith can almost be likened to currency, all initiate life with a measure of faith.
Romans 12:3 For I say, through the grace given to me, to everyone who is among you, not to think of himself more highly than he ought to think, but to think soberly, as God has dealt to each one a measure of faith.
This measure of faith that each of us were dealt by God is for us to discover the highest investment for. Love is the ideal target of faith; this transaction is to be demonstrated early in life by loving parents. A child learns to trust in the love of their parents and later in a loving God.
All men without exception spend their life searching for a worthy place to invest their faith. Many trust only themselves; their faith investment does not extend beyond the love that they hold for themselves. Others search for the love of a spouse or boyfriend and girlfriend. Some are in search of their kindred spirit but all are trusting, placing their faith in places that may or may not prove prudent.
We all know those that can no longer trust anyone, their faith has been bankrupt they no longer have faith to invest.
The Bible says that God’s love is the intended target for mankind’s love.
Ephesians 2:8 For by grace you have been saved through faith, and that not of yourselves; it is the gift of God,