The section of scripture that is referenced with respect to the unforgivable sin or blaspheme of the Holy Spirit is:
Mark 3:22-30 (ESV)
22 And the scribes who came down from Jerusalem were saying, “He is possessed by Beelzebul,” and “by the prince of demons he casts out the demons.”
23 And he called them to him and said to them in parables, “How can Satan cast out Satan?
24 If a kingdom is divided against itself, that kingdom cannot stand.
25 And if a house is divided against itself, that house will not be able to stand.
26 And if Satan has risen up against himself and is divided, he cannot stand, but is coming to an end.
27 But no one can enter a strong man’s house and plunder his goods, unless he first binds the strong man. Then indeed he may plunder his house.
28 “Truly, I say to you, all sins will be forgiven the children of man, and whatever blasphemies they utter,
29 but whoever blasphemes against the Holy Spirit never has forgiveness, but is guilty of an eternal sin”—
30 for they were saying, “He has an unclean spirit.”
It is clear from the context that the offence being spoken of is attributing a miracle of God, carried out with the power of/in the Holy Spirit and yet attributed unto Satan. Christ was countering that Satan doesn't drive out Satan and that a house divided will not stand against itself. The offense being referenced is in verse 22 where they claim it was the power of Satan at work.
Additionally the sentiment is carried forth in Hebrews in the following passage:
Hebrews 10:29-31 (ESV)
29 How much worse punishment, do you think, will be deserved by the one who has trampled underfoot the Son of God, and has profaned the blood of the covenant by which he was sanctified, and has outraged the Spirit of grace?
30 For we know him who said, “Vengeance is mine; I will repay.” And again, “The Lord will judge his people.”
31 It is a fearful thing to fall into the hands of the living God.
Here in Hebrews it is the saving blood of Christ that is being disparaged and made of no effect yet it is essentially the same thing and that is rejecting the deity of Christ/God/God's Holy Spirit.
If you want further reading about this passage of Hebrews I have copied one commentary regarding this passage:
Of how much sorer punishment—Such offenses were trifling in comparison of this, and in justice the punishment should be proportioned to the offense.
Trodden under foot the Son of God—Treated him with the utmost contempt and blasphemy.
The blood of the covenant—an unholy thing—The blood of the covenant means here the sacrificial death of Christ, by which the new covenant between God and man was ratified, sealed, and confirmed. And counting this unholy, or common, κοινον, intimates that they expected nothing from it in a sacrificial or atoning way. How near to those persons, and how near to their destruction, do they come in the present day who reject the atoning blood, and say, "that they expect no more benefit from the blood of Christ than they do from that of a cow or a sheep!" Is not this precisely the crime of which the apostle speaks here, and to which he tells us God would show no mercy?
Despite unto the Spirit of grace?—Hath insulted the Spirit of grace. The apostle means the Holy Spirit, whose gifts were bestowed in the first age on believers for the confirmation of the Gospel. See 6:4-6. Wherefore, if one apostatized in the first age, after having been witness to these miraculous gifts, much more after having possessed them himself, he must, like the scribes and Pharisees, have ascribed them to evil spirits; than which a greater indignity could not be done to the Spirit of God. Macknight. This is properly the sin against the Holy Ghost, which has no forgiveness.
Adam Clarke's Commentary.
again there are many interpretations regarding these thoughts but I believe that the scriptures here present the thoughts that are behind this most grievous of sins. That's not to say they are the only verses that reflect that sentiment or rejecting the deity of Christ/God/God's Holy Spirit but they are very clear ones and that is why I used them.
As for statements of conflict and conflicts in Scripture I believe that prayerful study and listening to God's teaching through His Holy Spirit will clear up many of what is thought to be conflicts and areas where it's felt that Scriptures contradict themselves. I am curious as to where you feel that the Bible has those contradictions and what they are?