That said, here is what I found helpful about The Sacred Search.
Thomas makes a critical point in simply saying that the most important aspect of discovering who you should marry is the convictions you have about marriage prior to ever entering a relationship. The sub-title says it all: What if it's not about who you marry, but why? That is worth the cost of the book. In particular, he is careful to question the common motive for entering a long-term, marriage-directed relationship: namely, emotion. I really appreciated how Thomas incisively critiqued, via Scripture, reason, and data, the dysfunction of letting emotion-driven infatuations govern lifelong choices, especially the one of marriage. This sets the stage for the remainder of the book, which advances the argument that big Biblical truths, while not emotion-less, are better arrived at by clear-headed, progressive decisions and thoughtful self-examination.
For instance, a major theme is that of character. One's spouse should be spiritually mature and emotionally healthy. If one is a serious Christian, then one should find someone committed to the mission and truths of gospel-driven life. From there, Thomas also suggests the wisdom of finding a spouse who shares secondary priorities as well, such as views on gender roles, parenting, and overall lifestyle. He also reminds us that the choices we make in marriage partners not only affect us, but future children, other family members, and our wider community.
The book ends with a tough challenge. Thomas invites readers to consider ending said questionable relationships that are not based in the truths for which he has been arguing. He states quite clearly that it is better to go through a messy dating break-up than enter into a lifelong marriage that is full of pain.
While I really appreciated Thomas's practical wisdom and penchant for clear-cut admonitions, let me identify areas where I would have preferred some additional nuance. First, Thomas makes a fairly large point that God does not have one person in particular set aside for us. He makes this point to discourage his audience from preoccupation with a specific person, rather than a godly and wise process of waiting and finding. However valid the ultimate point, it needs to be noticed that Thomas is making a significant theological claim. Now, when it comes to the prospect of God setting someone aside for us to marry, I would not suggest beating the drum of meticulous providence. But I would recommend against specific claims of how sovereignty factors into the big choices of life, one way or the other, just so no one gets sidetracked by a disputed point of theology. Thomas may end up distracting certain Calvinist-leaning young people, many of whom are spiritually and theologically predisposed to read this book and benefit from it.