Rahab may not be the first name that comes to mind when discussing courageous faith. She actually does.
There is a difference between belief and faith. We can believe FOR something or have faith IN Someone(Jesus). Faith is not having all the evidence but putting action to firm belief.
Hebrews 11:1 (AMPC) Now faith is the assurance (the confirmation, the title deed) of the things [we] hope for, being the proof of things [we] do not see and the conviction of their reality [faith perceiving as real fact what is not revealed to the senses].
She put action to her faith, believing that the Hebrew God was real and the True Living God, enough so that she took the risk.
We could all learn a lesson from her. She risked everything for faith in this previously unknown God of the Hebrews based solely on what she heard about Him.
Romans 10:17 So faith comes from hearing, and hearing by the word of Christ.