Jesus characterizes and contrasts the cost of repentance...and...the cost for failure to repent in Luke 20:18; "Whosoever shall fall upon that stone shall be broken; but on whomsoever it shall fall, it shall be ground to powder." What is Jesus saying? He is, as God always does, giving us two simple choices. We are reminded of that old Fram Filter (C) ad of some years back; "Pay me now or pay me later!" Either we die to self now and live eternally or live for self now and die eternally. This is the same essential message of Scripture from Genesis to Revelation. While God has different requirements in each of the three dispensations, the necessity of true repentance is present in all three.
Jesus Christ is the "stone which the builders rejected that has now become the chief cornerstone" of God's house. The builders (The Jews and their leaders) rejected that chief cornerstone and suffered destruction in 70 a.d. at the hands of Titus the Roman. Christ uses the metaphor to contrast the choices we have in the Christian age, what the Bible calls the "last days." We can either cast ourselves on the stone of Christ and be broken (true and total repentance) thus ending our lives to self while claiming eternal life or we can refuse to repent and suffer the penalty. What is that penalty? It is being crushed into "dust" by the stone resulting in total and eternal destruction, a destruction not unlike what happened to the Herodian Temple where "not one stone was left upon another." That temple, and those people, were crushed as it were, into dust. The "dust bin" of eternity is Satan's hell where all the "non-broken" people reside forever, many of whom were "good" people while on this earth. They just refused to be "broken on the stone."
Repentance, true repentance, requires a response to God's grace, mercy and His free gift of salvation. We must, as Peter said in Acts 2:38, be "baptized in the name of Jesus Christ for the remission of sins." One cannot "repent" while refusing baptism for this is the time and place of God's work - the removal of our sins much like circumcision of the old covenant. (Colossians 2:11-12) Repentance AND baptism constitute one's "falling upon that stone." "Repentance" without baptism is like announcing that you are going to cast yourself down upon the stone of Christ but then refusing to do so. Submission to God's will in baptism completes the process for that is when we join Christ in His death. (Romans 6:3) We become "broken upon the stone" in the watery grave where God meets us as we meet the blood of His dear son, blood that was "shed for the remission of sins."
What then shall it be for us? Will we be broken or will we be crushed by the stone of Christ into eternal dust? The "Rock of Ages" can save us or destroy us! Which will it be?