Romans 9:30-33

What shall we say then?—that the Gentiles who did not pursue righteousness obtained it, that is, a righteousness that is by faith,  but Israel even though pursuing a law of righteousness did not attain it.  Why not? Because they pursued it not by faith but (as if it were possible) by works. They stumbled over the stumbling stone,  just as it is written, “Look, I am laying in Zion a stone that will cause people to stumble and a rock that will make them fall, yet the one who believes in him will not be put to shame.”

There is a difference between building your own house, and entering into a house that has been built for you. I suppose there are some folks who would not be able to enter into something they hadn’t built themselves, and that is why Christ is the stumbling block. Our own efforts of paving the way to right relationship with God all break apart upon the cornerstone of Christ. Everything we inherit in eternal life hinges upon Him, and it is by grace through faith and not by works of the law. I heard it said once before, “Everything you need is bound up in the resurrected Savior”. Everything. There is not one stone you put in place to secure your relationship with God, you only enter into what Jesus has done for you. Through faith in Christ then, He empowers us and by The Holy Spirit we follow Him and assist in building His Kingdom.