Faith comes by HEARING and HEARING and HEARING the word of God or scriptures - Romans 10:17. So, God changed the darkness to light by SPEAKING words, which He BELIEVED and HEARING them - Genesis 1:3, Jesus changed a stormy situation to a calm situation by SPEAKING words, which He BELIEVED and HEARING them - Matthew 8:26, and Ephesians 5:1 says, 'be imitators of God, copy Him and follow His example, as children imitate their father'. So,  you too can overcome your doubt or change your darkness to light or change your stormy situations to calm situations by BELIEVING and then SPEAKING or READING the word or scriptures and HEARING and HEARING and HEARING, the word or scriptures daily.  

Christ who is in us, is greater than he(the Devil), who is in the world - 1 John 4:4(NKJV)

We do not waver at the promise of God, through unbelief, but we are strengthened in faith, giving glory to God and being fully convinced, that what He promised, He is also able to perform - Romans 4:20-21(NKJV) 

Because I believe, all things are possible for me - Mark 9:23(NKJV) 

To be continued