No, Carl Trueman isn't moving Romeward, but he has post listing reasons that he thinks people give for leaving (link to post). But the reasons given for leaving was not exactly the question posed to him. The question posed to him was the reasons that people leave for Rome. Trueman listed a lot of salient items, but I think he overlooked a few, and so I offer this as a supplement to his post.
1. Love of Idolatry
Men love idols. We can see this throughout the Old Testament and New Testament. It's especially clear in the Old Testament, in which not only are idols to be found in Lot's possession (and stolen by Rachel)[FN1], but an idol is made by the Israelites as soon as Moses seems to have disappeared [FN2]. The Israelites are repeatedly warned against the dangers of idolatry [FN3], and yet they return to it time and time again [FN4]. This is the case even despite a number of purges of idols, such as under Asa [FN5].
The New Testament likewise describes the pagan fondness for idolatry [FN6]. John's last words in his first catholic epistle are to warn his readers to avoid idolatry [FN7]. Likewise, arguing from the evil example of Israel, Paul exhorts the Corinthians to avoid idolatry [FN8].
It's a huge temptation, and the religion of Rome is rife with it. For example, the bread and wine are worshiped as though they are God [FN9]. The practice of praying before images and presenting gifts during such worship is also viewed as normal [FN10]. Moreover, Rome has endorsed the so-called Seventh Ecumenical Council, which mandated the use of images of Jesus Christ, Mary, angels, and the saints in churches [FN11].
It seems reasonable to conclude that people who join Rome, join it because they love its idolatry. They are not filled with a righteous indignation at this abominable practice, but instead find it alluring.
2. Love of Certainty
I cannot document or prove this item as thoroughly as the first. One thing that I have noticed, however, is that a number of Roman converts point to the issue of certainty. They seem to think that the only way one can have certainty about doctrine is if one has an infallible church. Their typical rationale is that there are thousands of different opinions about Scripture, and consequently they conclude that one cannot be certain about one's conclusions from Scripture, since there are so many who disagree. Two obvious flaws in their thinking are that there is no good reason to suppose that any infallible church exists and that although there may be thousands of opinions about what Scripture teaches, remarkably none of the groups that hold to Scripture alone as their authority arrive at something approximating Roman doctrines.
3. Escondido Movement
Under the topic of flawed ecclesiologies, Trueman rightly points a finger at "Emergent Christianity" and the "Federal Vision" but Trueman omits to address the Escondido movement. This movement reacts strongly to the Emergent phenomenon and to the Federal Vision, but often on quite weak terms (such as an over-reliance on the amended Westminster Confession). It tries to set itself forth as the official voice of "Reformed" even while departing from the Reformers on a number of significant points. There needs to be a response to Rome's flawed ecclesiology, but that response cannot take the form of trying to provide a Reformed "Rome lite" where excommunication is viewed as being an exercise of power rather than a recognition of apostasy, where our amended (!) confessions become a rule of faith, and where Scriptural exegesis in debates over issues that the confession addresses are rare or secondary to the issue.
We need to recover the grammatical-historical hermeneutic more than we need to recover the Reformed confessions. We need to understand the importance of church discipline, and make sure it is properly applied. We need to make sure that the fundamentals of the faith are defended, Scripture is explained from the pulpit, and charity is extended in as many of the non-essentials as we can.
Of course, none of the failures of the Escondido movement would justify a departure to Rome. Rome's ecclesiological problems dwarf anything one can find in any other church. An earthly head of the church who claims to be Christ's vicar? Come on! A church that claims to have the gift of infallibility, and yet can't tell itself which (if either!) of Molinism or Thomism is correct. A move from an Escondido-style church to Rome is not a jump from the frying pan into the fire, it's a move from a cat with slight halitosis to a rabid lion.
Do I echo many of Trueman's concerns? Absolutely. I haven't spent this post repeating his points or patting him on the back. I hope he gets plenty of that already. I'm simply writing to emphasize a few points that he may have overlooked.
1) Genesis 31:19 And Laban went to shear his sheep: and Rachel had stolen the images that were her father's.
2) Exodus 32:23-24 For they said unto me, Make us gods, which shall go before us: for as for this Moses, the man that brought us up out of the land of Egypt, we wot not what is become of him. And I said unto them, Whosoever hath any gold, let them break it off. So they gave it me: then I cast it into the fire, and there came out this calf.
3) Leviticus 19:4 Turn ye not unto idols, nor make to yourselves molten gods: I am the LORD your God. | Leviticus 26:1 Ye shall make you no idols nor graven image, neither rear you up a standing image, neither shall ye set up any image of stone in your land, to bow down unto it: for I am the LORD your God.
4) Isaiah 57:5 Enflaming yourselves with idols under every green tree, slaying the children in the valleys under the clifts of the rocks?
5) 1 Kings 15:11-13 And Asa did that which was right in the eyes of the LORD, as did David his father. And he took away the sodomites out of the land, and removed all the idols that his fathers had made. And also Maachah his mother, even her he removed from being queen, because she had made an idol in a grove; and Asa destroyed her idol, and burnt it by the brook Kidron.
6) Acts 17:16 Now while Paul waited for them at Athens, his spirit was stirred in him, when he saw the city wholly given to idolatry.
7) 1 John 5:21 Little children, keep yourselves from idols. Amen.
8) 1 Corinthians 10:1-14
Moreover, brethren, I would not that ye should be ignorant, how that all our fathers were under the cloud, and all passed through the sea; and were all baptized unto Moses in the cloud and in the sea; and did all eat the same spiritual meat; and did all drink the same spiritual drink: for they drank of that spiritual Rock that followed them: and that Rock was Christ. But with many of them God was not well pleased: for they were overthrown in the wilderness. Now these things were our examples, to the intent we should not lust after evil things, as they also lusted. Neither be ye idolaters, as were some of them; as it is written, The people sat down to eat and drink, and rose up to play [Exodus 32:6]. Neither let us commit fornication, as some of them committed, and fell in one day three and twenty thousand. Neither let us tempt Christ, as some of them also tempted, and were destroyed of serpents. Neither murmur ye, as some of them also murmured, and were destroyed of the destroyer. Now all these things happened unto them for ensamples: and they are written for our admonition, upon whom the ends of the world are come. Wherefore let him that thinketh he standeth take heed lest he fall. There hath no temptation taken you but such as is common to man: but God is faithful, who will not suffer you to be tempted above that ye are able; but will with the temptation also make a way to escape, that ye may be able to bear ihttp://www.blogger.com/img/blank.gift. Wherefore, my dearly beloved, flee from idolatry.
9) CCC 1378 "Worship of the Eucharist. In the liturgy of the Mass we express our faith in the real presence of Christ under the species of bread and wine by, among other ways, genuflecting or bowing deeply as a sign of adoration of the Lord. 'The Catholic Church has always offered and still offers to the sacrament of the Eucharist the cult of adoration, not only during Mass, but also outside of it, reserving the consecrated hosts with the utmost care, exposing them to the solemn veneration of the faithful, and carrying them in procession.'"
10) "I am pleased to have the opportunity to pray before her image, brhttp://www.blogger.com/img/blank.gifought here specially from Gozo for this occasion. I am also delighted to present a Golden Rose to her, as a sign of our shared filial affection for the Mother of God." (source)
11) "We define the rule with all accuracy and diligence, in a manner not unlike that befitting the shape of the precious and vivifying Cross, that the venerable and holy icons, painted or mosaic, or made of any other suitable material, be placed in the holy churches of God upon sacred vessels and vestments, walls and panels, houses and streets, both of our Lord and God and Savior Jesus Christ, and of our intemerate Lady the holy Theotoke, and also of the precious Angels, and of all Saints." (source)