Monergism

“The sin of Adam did not make the condemnation of all men merely possible; it was the ground of their actual condemnation. So the righteousness of Christ did not make the salvation of men merely possible, it secured the actual salvation of those for whom He wrought.”
~ Charles Hodge

"Irresistible grace presupposes particular redemption. There is no such grace apart from Christ and His work. (Eph 1:3, 1 Pet. 1:3) Therefore, so-called four-point Calvinism is untenable."
John Hendryx

So-called four-point Calvinism fails the test of biblical Christocentricity and, as such, tends to view TULIP as an abstraction rather than centering on Christ. The TULIP only makes sense when Christ is found at its center. Consider the TULIP as a chiasm with the "L" at the top of the pyramid. All grace has its source in Jesus Christ, from whom all redemptive blessings flow. The other doctrines have no power apart from Christ.
John Hendryx

"Wherefore all theology, when separated from Christ, is not only vain and confused, but is also mad, deceitful, and spurious; for, though the philosophers sometimes utter excellent sayings, yet they have nothing but what is short-lived, and even mixed up with wicked and erroneous sentiments."
- John Calvin

The extent of the atonement is defined by the intent of the atonement.” (Matt 1:21; John 17:2,9, 24)
~Steven Lawson

And they sang a new song: "You are worthy to take the scroll and to open its seals, because you were slain, and with your blood you purchased men for God from every tribe and language and people and nation. You have made them to be a kingdom and priests to serve our God, and they will reign on the earth.
Revelation 5:9-10

Since therefore the children share in flesh and blood, he himself likewise partook of the same things, that through death he might destroy the one who has the power of death, that is, the devil, and deliver all those who through fear of death were subject to lifelong slavery. For surely it is not angels that he helps, but he helps the offspring of Abraham.
Hebrews 2:14-16

Let us remember, on the other hand, that while life is promised universally to all who believe in Christ, still faith is not common to all. For Christ is made known and held out to the view of all, but the elect alone are they whose eyes God opens, that they may seek him by faith. Here, too, is displayed a wonderful effect of faith; for by it we receive Christ such as he is given to us by the Father -- that is, as having freed us from the condemnation of eternal death, and made us heirs of eternal life, because, by the sacrifice of his death, he has atoned for our sins, that nothing may prevent God from acknowledging us as his sons. Since, therefore, faith embraces Christ, with the efficacy of his death and the fruit of his resurrection, we need not wonder if by it we obtain likewise the life of Christ.
John Calvin Commentary on John 3:16

The Arminians say, 'Christ died for all men.' Ask them what they mean by it. Did Christ die so as to secure the salvation of all men? They say, 'No, certainly not.' We ask them the next question: Did Christ die so as to secure the salvation of any man in particular? They answer 'No.' They are obliged to admit this, if they are consistent. They say, 'No; Christ has died that any man may be saved if ?' and then follow certain conditions of salvation. Now, who is it that limits the death of Christ? Why, you. You say that Christ did not die so as infallibly to secure the salvation of anybody. We beg your pardon, when you say we limit Christ's death; we say, 'No, my dear sir, it is you that do it.' We say Christ so died that he infallibly secured the salvation of a multitude that no man can number, who through Christ's death not only may be saved, but are saved, must be saved and cannot by any possibility run the hazard of being anything but saved. You are welcome to your atonement; you may keep it. We will never renounce ours for the sake of it.
Charles Spurgeon