Perseverance of the elects ---vs--- blasphemy against the Spirit according to Calvinist?

The general answer to this is that the Calvinist has the proposition that all true believers will persevere and thus not lose salvation. Because the (hyper)Calvinist usually sees God as the primary causal agent of salvation, loss of salvation isn't possible since God will effect the perseverance.

The Calvinist struggles with counter-examples. But in Romans 11:22 one must first prove that being "cut off" refers to loss of salvation. Another option is that it refers to being "cut off" from the tree of blessing. So a Christian can experience salvation, but fail to experience full blessing, like the unrewarded believer of 1Cor3:15.

As to the blasphemy of the Holy Spirit, it's better to see that this is the primary difference between the believer and unbeliever. The unbeliever saw Jesus' works and yet didn't credit them as coming from the Holy Spirit. Unbelief in Jesus is blasphemy of the Holy Spirit. However, even a believer in Jesus can speak a word against Jesus. Peter did this when he denied Christ. A believer doesn't blaspheme the Holy Spirit (because he has believed) but he can fail to live fully up to this belief, and thus sometimes speak a word against Jesus. This is a difference between initial salvation from the penalty of sin and ongoing salvation from the power of sin.

For the Calvinist, blasphemy is impossible for the elect while forgiveness is impossible for the non-elect. But a Calvinist will recognize that all who are elect will believe, so there is no category of non-elect believer or elect non-believer.

Rather than seeing salvation as deterministic only by God, a more balanced approach is to see that God's sovereignty (per Calvinism) includes the free belief of humanity. This allows for the truth that eternal life (salvation) can never be lost, even when we are sometimes faithless (2Tim2:11-13).

Every effect has a cause (except God Himself).

Effect: The elect will persevere and be saved.

Causes:

1. The Word of God
2. The Holy Spirit
3. The Providence of God

The warning verses are an essential part of the role that Word of God plays in effecting the salvation of the elect. Matthew 13 says:

3 Then he told them many things in parables, saying: “A farmer went out to sow his seed. 4 As he was scattering the seed, some fell along the path, and the birds came and ate it up. 5 Some fell on rocky places, where it did not have much soil. It sprang up quickly, because the soil was shallow. 6 But when the sun came up, the plants were scorched, and they withered because they had no root. 7 Other seed fell among thorns, which grew up and choked the plants. 8 Still other seed fell on good soil, where it produced a crop—a hundred, sixty or thirty times what was sown. 9 Whoever has ears, let them hear.”

The words of warning fall on the good soil in the heart of the elect and produce a crop. That crop includes perseverance.

For a reference to a Calvinist website that makes this argument, see:

https://www.monergism.com/blog/what-does-it-mean-fall-away

A quote from that site:

The warnings in scripture given in the context of the visible church are directed at both the regenerate and unregenerate, both wheat and tares, both sheep and goats. These kind of warnings serve two purposes:

1) The elect (sheep) hear his voice in the word and take heed.

2) The non-elect (goats) do not hear his voice and fall away.

In other words, the warnings serve as a means of grace (or hardening). - when the elect hear warnings in scripture it causes them to persevere. When the non-elect hear it, their heart hardens over time and they fall away completely, revealing that they have been trusting in something other than Christ alone for salvation.