Why did God allow for the striking-down of people in the Old Testament? How is this reconciled with the dogma of a loving God?
Protestants and modern-day “Jews” don’t have an answer for this — one beyond dualism or “mystery”, I mean. But the Church does.
There is mortal sin, and there is venial sin (1 John 5:17). Mortal sin — willful and of grave nature — separates one from God, practically killing the soul. Venial sin — all other — must simply be cleansed, and it does not eternally separate us from Him. And this distinction is shown in the Old Testament.
Among mortal sins punished: irreverence (2 Samuel 6:1-7), despair/disbelief (Numbers 11:1-3), and false claims of authority (Numbers 16). These crimes have always been condemned.
Why did punishment change from body-centric to soul-centric? First, it didn’t, because unrighteous people were also kept from entering the Limbo of the Patriarchs, which, after Christ’s Sacrifice, later led to Heaven. Second, temporal punishment was the only way to get at the Jews’ consciences: As liberal scholars love to point out, the majority of Jews did not believe in an afterlife!
God does not desire death, though it can be used to give us the best chance at salvation (2 Peter 3). (I think here of St. Rita and her sons.) Even in the old days, He merely wanted a contrite heart (Psalm 51:17), and He wanted devotion.
There is no change in principle: God is immutable.
The Church is my greatest weight. Of course, the weight of over a billion souls would likely be rather large, especially post-McDonald’s, so I suppose that nothing else is really comparable.
What does this mean? In an age of moral relativism, instability, and self-gratification, much like the age of the Roman Empire prior to its Christian conversion, I found myself alone and empty after a scarring experience. So, I sought the counsel of philosophy and history – surely, men had answered my questions before! – and I was, after seemingly endless struggles with myself and others, eventually comforted. The Church became vindicated in my heart.
The more I study, the more I am forced to accept Catholicism as the true Faith. The depth and size of it, as well as its impacts on culture, force any serious student to step back and pay at least a bit of attention. It took me a while to overcome my initial ambivalence toward any religion in particular – though I was always appreciative of God and enamored with the subject in general – but once I had crossed the proverbial Tiber, there was no going back.
I was baptized Catholic, and I vaguely recall some crossing with holy water and lighting prayer candles, but I was hardly raised to practice the Faith. In high school, I dug into a box of things from my infancy. I spotted a rosary within it, along with a note saying that it belonged to my great-grandmother. I mentioned it to a Catholic friend, and he gave me some information about it. That set of events started the arduous process of reconciliation.
Later, at the urging of the aforementioned friend, I casually flipped through the writings of the Church Fathers (prominent ancient Christian leaders). I quickly became impressed. I only did this, originally, to assuage my ego. I had made a theological speculation, and he answered me with, “Well, did the early Christians believe that?” I did not know. Anyway, he was right, and I was wrong.
My advice for anyone that wishes to be a Protestant is to avoid the Church Fathers like one would avoid a plague. I once remarked to a professor that introducing the former to the latter is like shaking a baby: it might teach them a lesson, but it also might kill them.
In my search for the Truth (capital ‘T’ intended), I asked a long series of questions.
On the Magisterium (teaching authority) of the Church, I asked: Does God still reveal things to us, or does His message end with the Bible? What would He reveal things through?
The idea that God arbitrarily ended His message with the Bible and deliberately chose to allow confusion over doctrine became untenable to me, especially in light of verses like Deuteronomy 31:6 (He will never leave us) and John 17:11 (He requests Christian unity). The Protestant position on this (Sola Scriptura) then made little sense. How could that idea, unprecedented before the Renaissance and ungrounded in Tradition or common sense, be true? I have found no sensible argument in favor of it.
What would His mouthpiece be, though? His Bride (Mark 2:18-20), the Church, of course! As a wife understands the workings of her husband, so does the Church understand Christ. From there, how is She structured? This is where apostolic succession (the lineage of bishops from the time of the Apostles to the present) comes in. Bishops are given special power (Luke 21:15) – which even Simon Magus knew was handed down (Acts 8:18-19) – after the laying on of hands (1 Timothy 4:14; 2 Timothy 1:6) in their consecration ceremonies. They can trace themselves back to the very beginning of Christianity. All of this “clicked” in my head when I first read these words from St. Ignatius of Antioch: “See that you all follow the bishop, even as Jesus Christ does the Father, and the presbytery as you would the apostles; and reverence the deacons, as being the institution of God. Let no man do anything connected with the Church without the bishop.”
Now, who leads it? This is answered by Matthew 16:18, the famous verse, which helped me grasp that Christ built His Church on Peter (aka Cephas), the faithful “rock” (Greek, Aramaic). It’s a parallel to the story of Eliakim (Isaiah 22:20-22), who represented his king. St. Peter, called by Christ to “feed [His] sheep” (John 21:17), likewise represented his King. Some in the historical-critical movement have, naturally, raised objections to St. Peter’s primacy. But even agnostic Protestant historian John Julius Norwich wrote of the pope, “It seems more likely than not that St. Peter did in fact come to Rome and was martyred there, probably somewhere on the Vatican Hill…[and] there can be little doubt that he was the generally acknowledged leader of Christ’s disciples.” Whenever I doubt, I latch on to this information: the historical basis for the Papacy is rock-solid.
My goal is to increase the powers and jurisdiction of this great entity to the fullest capacity, because I recognize the impact that She has had and can have on the world. Documents like Humanae Vitae and Evangelium Vitae urge respect for the sanctity of life, Rerum Novarum and Quadragesimo Anno offer economic principles rooted in good morals, and so on. If only humanity would follow the path that the Church has set forth! This temporal aspect, even by itself, is enough to drive me, despite how burdensome this desire can be.
In conclusion, I will leave the reader with a quote from G. K. Chesterton. “The difficulty of explaining ‘why I am a Catholic’ is that there are ten thousand reasons all amounting to one reason: that Catholicism is true.”
For Protestantism to make much sense, the Church must have, at some point, abandoned the truth and become apostate. Otherwise, Protestantism has no license to exist. But when was this “Great Apostasy”? Protestants offer varying opinions, but none of them hold up to scrutiny.
Was it right after the deaths of the Apostles?
A view most supported by Mormons and Jehovah’s Witnesses is that, after the Apostles, the Church quickly fell into apostasy. This would be a massive blow at both God’s promise to guard His Church (Joshua 1:5; Matthew 16:18) and all of the doctrine mentioned hereafter. But if this were true, would not one of the disciples of the Apostles have spoken out? We have writings from many of them, including Pope St. Clement I, St. Barnabas, St. Polycarp, and St. Ignatius of Antioch. None of them mention a “Great Apostasy”. But even if we indulge the other side and admit the possibility that even these men fell away, we still have early documents and creeds (like the Didache) that were probably formulated under the authority of the Apostles. Because Christians continued to be in accord with these extra-Biblical teachings, we know that they must have been in accord with the true Church.
Was it at the time of Constantine?
A semi-popular view is that Constantine corrupted Christianity by encouraging “pagan” elements and demanding a decision from the First Council of Nicaea. This is the view that I come into contact with most often, but it is also the most problematic. If the Church became apostate by 337 (the year of Constantine’s death), then the Biblical canon – which only really started to be compiled by St. Athanasius in 367 – may be wrong: we would have no assurance of its infallibility. Also, on top of that, all later theology would be necessarily nulled.
Was it during the Middle Ages?
The possibility of an apostasy in Medieval times seems far-fetched, too. This theory revolves, primarily, around hatred for some “bad” popes. Rather than focusing on doctrinal issues, proponents of this theory typically resort to character defamation. Many attack the Crusades, which tamed a fanatic Islam, and such. But in this period, literacy rates increased, art flourished, the university system developed, laws were better-codified, and the Bible became more accessible to lay people [1, 2]. The only seemingly objectionable doctrinal development was Pope Boniface VIII’s declaration, “Outside of the Church, there is neither salvation nor the remission of sins”, but even this originates with St. Cyprian! The teaching relates to: 1) the fact that baptism (whether by water, blood, or desire) brings one into the Church (even if done within a Protestant community), because the sacrament was entrusted to Her and She allows anyone with the right intent to perform it, and 2) the importance of conscience and the dangers of apostasy. Nothing worthy of damnation here!
Was it just before the “Reformation”?
The idea of a “restoration” being needed just before the “Reformation” also seems improbable. This common idea is based on the “selling” of indulgences [1, 2, 3] (Martin Luther attacks the practice multiple times in his Ninety-Five Theses), but is mostly due to a misunderstanding. Again, the Protestant understanding usually relies on the assault of characters: people like Johann Tetzel are demonized — perhaps rightfully — for abusing the system. But this abuse was not a doctrinal problem of the Church; rather, it was a disciplinary problem of men. Indulgences simply remove the temporal punishment due for past sin — they are not a “Get out of Hell free” card — and even when they were “sold,” they required some sort of penance. Indulgences only have a salvatory effectiveness (remittance of time in Purgatory) if the recipient is already destined for Heaven. So, it would seem that the fuss is all about nothing.
In conclusion, I see none of these options as likely.
Martin Luther said and wrote many heretical things, but here are a mere five quotes, along with Biblical passages that disprove them.
1. “For reason is directly opposed to faith. This is why you must let reason go. It must be killed and buried in believers.” 
(Answer: Proverbs 14:15, Colossians 1:9, Colossians 4:5-6, 1 Thessalonians 5:19-22)
2. “..[A Christian] could not lose his salvation, however much he sinned, unless he refused to believe. For no sin can condemn him save unbelief alone.” 
(Answer: Hebrews 10:26-27)
3. “Be a sinner, and let your sins be strong, but let your trust in Christ be stronger, and rejoice in Christ who is the victor over sin, death, and the world. We will commit sins while we are here, for this life is not a place where justice resides. …No sin can separate us from Him, even if we were to kill or commit adultery thousands of times each day.” 
(Answer: Psalm 4:4, Matthew 5:48, Hebrews 10:26-27)
4. “It is good that we have such a man [Jesus Christ], because God in himself is cruel and bad.” 
(Answer: Psalm 51:1, Jeremiah 9:24, Jeremiah 31:3)
5. “I miss more than one thing in this book [Revelation, aka Apocalypse], and this makes me hold it to be neither apostolic nor prophetic…and [I] can nohow detect that the Holy Spirit produced it. …My spirit cannot fit itself into this book.” 
(Answer: Revelation 22:19)
1. Luther’s Sermon on Matthew 19:13-15. “What Luther Says,” 1:485-486 (entry 1440). [link]
3. Let Your Sins Be Strong: A Letter From Luther to Melanchthon. Translated by Erika Bullmann Flores. [link]
5. M. Reu, Luther’s German Bible: An Historical Presentation Together with a collection of Sources (Ohio: The Lutheran Book Concern, 1934) 174-175 [link]