Romans 9:32

And why not? Because it was not by faith [that they pursued it], but as though it were by works [relying on the merit of their works instead of their faith]. They stumbled over the stumbling Stone [Jesus Christ].

1 Peter 2:8

and,“A stone of stumbling and a rock of offense”; for they stumble because they disobey the word [of God], and to this they [who reject Him as Savior] were also appointed.

Matthew 13:57

And they took offense at Him [refusing to believe in Him]. But Jesus said to them, “A prophet is not without honor except in his hometown and in his own household.”

Matthew 19:16-20

And someone came to Him and said, “Teacher, what [essentially] good thing shall I do to obtain eternal life [that is, eternal salvation in the Messiah’s kingdom]?”

Luke 2:34

Simeon blessed them and said to Mary His mother, “Listen carefully: this Child is appointed and destined for the fall and rise of many in Israel, and for a sign that is to be opposed—

Luke 7:23

Blessed [joyful, spiritually favored] is he who does not take offense at Me.”

John 6:27-29

Do not work for food that perishes, but for food that endures [and leads] to eternal life, which the Son of Man will give you; for God the Father has authorized Him and put His seal on Him.”

Acts 16:30-34

and after he brought them out [of the inner prison], he said, “Sirs, what must I do to be saved?”

Romans 4:16

Therefore, [inheriting] the promise depends entirely on faith [that is, confident trust in the unseen God], in order that it may be given as an act of grace [His unmerited favor and mercy], so that the promise will be [legally] guaranteed to all the descendants [of Abraham]—not only for those [Jewish believers] who keep the Law, but also for those [Gentile believers] who share the faith of Abraham, who is the [spiritual] father of us all—

Romans 10:3

For not knowing about God’s righteousness [which is based on faith], and seeking to establish their own [righteousness based on works], they did not submit to God’s righteousness.

Romans 11:11

So I say, have they stumbled so as to fall [to spiritual ruin]? Certainly not! But by their transgression [their rejection of the Messiah] salvation has come to the Gentiles, to make Israel jealous [when they realize what they have forfeited].

1 Corinthians 1:23

but we preach Christ crucified, [a message which is] to Jews a stumbling block [that provokes their opposition], and to Gentiles foolishness [just utter nonsense],

1 John 5:9-12

If we accept [as we do] the testimony of men [that is, if we are willing to take the sworn statements of fallible humans as evidence], the testimony of God is greater [far more authoritative]; for this is the testimony of God, that He has testified regarding His Son.

Treasury of Scripture Knowledge

Summary

Wherefore? Because they sought it not by faith, but as it were by the works of the law. For they stumbled at that stumblingstone;

Bible References

Because

Romans 4:16
Therefore, [inheriting] the promise depends entirely on faith [that is, confident trust in the unseen God], in order that it may be given as an act of grace [His unmerited favor and mercy], so that the promise will be [legally] guaranteed to all the descendants [of Abraham]—not only for those [Jewish believers] who keep the Law, but also for those [Gentile believers] who share the faith of Abraham, who is the [spiritual] father of us all—
Romans 10:3
For not knowing about God’s righteousness [which is based on faith], and seeking to establish their own [righteousness based on works], they did not submit to God’s righteousness.
Matthew 19:16
And someone came to Him and said, “Teacher, what [essentially] good thing shall I do to obtain eternal life [that is, eternal salvation in the Messiah’s kingdom]?”
John 6:27
Do not work for food that perishes, but for food that endures [and leads] to eternal life, which the Son of Man will give you; for God the Father has authorized Him and put His seal on Him.”
Acts 16:30
and after he brought them out [of the inner prison], he said, “Sirs, what must I do to be saved?”
1 John 5:9
If we accept [as we do] the testimony of men [that is, if we are willing to take the sworn statements of fallible humans as evidence], the testimony of God is greater [far more authoritative]; for this is the testimony of God, that He has testified regarding His Son.

They stumbled

Romans 11:11
So I say, have they stumbled so as to fall [to spiritual ruin]? Certainly not! But by their transgression [their rejection of the Messiah] salvation has come to the Gentiles, to make Israel jealous [when they realize what they have forfeited].
Matthew 13:57
And they took offense at Him [refusing to believe in Him]. But Jesus said to them, “A prophet is not without honor except in his hometown and in his own household.”
Luke 2:34
Simeon blessed them and said to Mary His mother, “Listen carefully: this Child is appointed and destined for the fall and rise of many in Israel, and for a sign that is to be opposed—
Luke 7:23
Blessed [joyful, spiritually favored] is he who does not take offense at Me.”
1 Corinthians 1:23
but we preach Christ crucified, [a message which is] to Jews a stumbling block [that provokes their opposition], and to Gentiles foolishness [just utter nonsense],

General references

Matthew 19:30
But many who are first [in this world] will be last [in the world to come]; and the last, first.
Mark 10:31
But many who are first will be last, and the last, first.”
Luke 7:23
Blessed [joyful, spiritually favored] is he who does not take offense at Me.”
Romans 4:4
Now to a laborer, his wages are not credited as a favor or a gift, but as an obligation [something owed to him].