The three patriarchs, Abraham, Jacob and Joseph, walk through different life experience, and each of them has a characteristic understanding of faith. Their faith is showed from different facet and represents their opinion towards God. Nevertheless, of all these three patriarchs, faith is that believing in God's power and following God's shepherd no matter what may betide. Faith to Abraham is that following God's order no matter what things look like in surface. One important point is that he took his family from Haran to Canaan. It was not a bad surrounding in Haran, and nobody knew if Canaan is truly as good as God described, but Abraham just followed God's shepherd and moved. Generally, it needs a lot of courage to give up existing good things and seek for a mirage-like description, so Abraham's undoubtedly agreement shows how deep he trusted God. Besides this, Abraham let Lot choose destination before him is also a certification of his faith. At a glance, the plain of Jordan is well watered so most people, like Lot, would be attracted. But Abraham believed that God would give him the best land just as he promised, so he allowed Lot to stay in Jordan. Lot believed in what is appealing to his eyes, but Abraham believed God's words, so Abraham was credited as righteousness (Genesis 15:6). What's more, the sacrifice of his son shows Abraham's deep faith significantly. For a old man, the offspring is the precious extension of his life, but this man can give up his closest relative to God, just because he put God at the highest position of the heart, and so that he was rewarded. He followed God's instruction, even if with sorrow and confusion, believed God's kindness, and trusted that he would make things good. So, following God's order and trusting him, is Abraham's definition of faith.
Jacob's faith, unlike other patriarchs, experiences a long journey to trust God whole-heartedly, but he never doubts God's holy power.