'Convinced' in the Bible

and if you are convinced that you are a guide for the blind, a light to those in darkness,

being absolutely convinced that God would do what he had promised.

For I am convinced that neither death, nor life, nor angels, nor rulers, nor things present, nor things to come, nor powers,

One person decides in favor of one day over another, while another person decides that all days are the same. Let each one be fully convinced in his own mind:

I myself am convinced, my brothers, that you yourselves are filled with goodness and full of all the knowledge you need to be able to instruct each other.