"For this is contained in Scripture: 'Behold, I lay in Zion a choice stone, a precious corner stone, and he who believes in Him will not be disappointed.' This precious value, then, is for you who believe; but for those who disbelieve, 'the stone which the builders rejected, this became the very corner stone,' and 'a stone of stumbling and a rock of offense'; for they stumble because they are disobedient to the word, and to this doom they were also appointed." (1 Peter 2:6-8)Christianity, at its core, is not about a creed or a manor of life, it is about a person and our relationship to Him. When the apostles when throughout the world, the did not go simply to teach a new doctrine or to persuade people to adopt a new belief system, they went to introduce people to a person; one who has become the corner stone, one who, if a person builds their lives upon Him, they would never be disappointed. For us who have believed, Jesus has become very precious, He has become our redeemer, our savior, and the very foundation of our lives, beliefs, and obedience. However, for those who have rejected Him, He has become a rock of offense and a rock of stumbling. Notice that they stumble over Him because they are disobedient to the word. Once being introduced to Jesus we have the choice of whether or not to make Him the corner stone of our lives; we much chose whether or not to make Him Lord of our lives and this means choosing whether or not to obey Him. If we are in relationship with Jesus then we ought to obey Him. However, while many people want Jesus, they still want to live lives on their own terms. They are like the men in the parable who said, "We will not have this man to reign over us." (Luke 19:14 NKJV) You cannot possess the corner stone and yet build your life your own way, you must obey the corner stone and build your life in right relationship with Him.
"But you are a chosen race, a royal priesthood, a holy nation, a people for God's own possession, so that you may proclaim the excellencies of Him who has called you out of darkness into His marvelous light; for you once were not a people, but now you are the people of God; you had not received mercy, but now you have received mercy." (1 Peter 2:9-10)
We must take care not to boast in whom we have become, for it was not by our own strength or righteousness that we have become great in the Kingdom of God but it was God who found us, who chose us, and who made us what we were not; we were not a people yet He made us a people, we had not received mercy yet He showered His mercy on us. All this working is from God and not ourselves, and God did this for a purpose, that we might show forth both the power and the love of God for mankind. Our lives are to be living testimonies of the goodness of God. People should be able to see in our lives the working of God, a working that only God can do, a working that is beyond all human strength and ability.
"Beloved, I urge you as aliens and strangers to abstain from fleshly lusts which wage war against the soul. Keep your behavior excellent among the Gentiles, so that in the thing in which they slander you as evildoers, they may because of your good deeds, as they observe them, glorify God in the day of visitation." (1 Peter 2:11-12)
Our lives are meant to bring glory to God, therefor it behooves us to adopt a lifestyle that is in keeping with the goodness and holiness of God. Paul put it this way, "I implore you to walk in a manner worthy of the calling with which you have been called." (Ephesians 4:1) We must live our lives like people are watching us, because they are; they are watching to see if our message is true, to see if God is really powerful enough to change a life, and to see if God can be trusted. Many people will make a decision regarding Jesus based on what they see more than what they here. We must never by like those whom Paul said, "the name of God is blasphemed among the Gentiles because of you." (Romans 2:24 NKJV)