As we read the Bible and encounter the saints who walk on its pages, there is none who compares to the man of Genesis known as Abraham. He is not regarded as a spiritual giant because of his knowledge of theological matters, or his wisdom in making decisions which affected those around him, or the fact that his actions always reflected carefully thought out obedience to God. It had nothing to do with keeping the Jewish law since it was not in existence at the time he did his living. Neither did it have anything to do with what he wore, or any markings on his body.
When Paul wrote to the Roman Christians, many of whom were Jewish by birth, he spoke of what made Abraham the spiritual giant of their heritage as he wrote, "What does the scripture say? 'Abraham believed God, and it was reckoned to him as righteousness.' " (Romans 4:3, Genesis 15:6). We sometimes overlook this simple fact about this great man of God. What enabled him to walk in a right relationship with God was his trust, his faith, his dependence on God to do what He said He would do.
What we know from living our own life and walking our own walk of faith is that this business of faith is no easy thing. It would be easier for some of us if we could just have our righteousness determined by the number of times we have attended church, or the cross we wear around our neck. Righteous faith is about depending on God when there is no rational reason to depend on Him. Being a very old man and living with a promise of many descendants is an example of depending on God to do what is not rational to believe is possible. It is easier to talk about depending on God while planning our own way out just in case God does not do as He has promised to do.