'Believe' in the Bible

For what if some did not believe? shall their unbelief make the faith of God without effect?

Even the righteousness of God which is by faith of Jesus Christ unto all and upon all them that believe: for there is no difference:

And he received the sign of circumcision, a seal of the righteousness of the faith which he had yet being uncircumcised: that he might be the father of all them that believe, though they be not circumcised; that righteousness might be imputed unto them also:

But for us also, to whom it shall be imputed, if we believe on him that raised up Jesus our Lord from the dead;

Now if we be dead with Christ, we believe that we shall also live with him:

That if thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved.

How then shall they call on him in whom they have not believed? and how shall they believe in him of whom they have not heard? and how shall they hear without a preacher?

That I may be delivered from them that do not believe in Judaea; and that my service which I have for Jerusalem may be accepted of the saints;