Isaiah 46:11
Calling a ravenous bird from the east, the man that executeth my counsel from a far country: yea, I have spoken it, I will also bring it to pass; I have purposed it, I will also do it. Calling a ravenous bird from the east, the man that executeth my counsel from a far country: yea, I have spoken it, I will also bring it to pass; I have purposed it, I will also do it.
God will do just as He has said He would do, bringing to pass what He has spoken and performing what He has purposed. Every promise He has made is therefore certain to be fulfilled. His promises are to be believed and received with confidence in that certainty.
This certainty gives reason for good courage. Troubled and doubting souls should not fear but believe. They should talk faith and walk by faith onward and forward and upward.