Of all the tales in the Bible (the majority of which I have learned through cultural osmosis and research, not for being a believer), one of the ones that I find most compelling is the one concerning Saint Thomas. The story is collected only in the Gospel of John, which is often seen referred to as the most “mystical” or “symbolic” of the gospels, and shares no common source with the other three gospels. The story, widely represented in art and rendered over and over again in multiple retellings, goes as follows: after Jesus dies and resurrects, the women who had been tending to his body, alert the Apostles. Thomas is one of these Twelve Apostles, and though Jesus gives them the Holy Spirit, Thomas wasn’t there at the time (John 20:24-28, English Standard Version):

“Now Thomas, one of the twelve, called the Twin, was not with them when Jesus came. So the other disciples told him, “We have seen the Lord.” But he said to them, “Unless I see in his hands the mark of the nails, and place my finger into the mark of the nails, and place my hand into his side, I will never believe.” Eight days later, his disciples were inside again, and Thomas was with them. Although the doors were locked, Jesus came and stood among them and said, “Peace be with you.” Then he said to Thomas, “Put your finger here, and see my hands; and put out your hand, and place it on my side. Do not disbelieve, but believe.” Thomas answered him, “My Lord and my God!”

After this incident, Thomas is kind of scolded for his doubt: Jesus said to him, “Have you believed because you have seen me? Blessed are those who have not seen and yet have believed.” (John 20:29, ESV)

Thomas’ incredulity is supposed to teach us that we should believe without seeing, but I love this story because Thomas’ failure to believe his eyes, to believe good news until he has felt definitive proof, is a deeply human thing. While the story is trying to teach a lesson on the positives of “blind” faith, it can be read as a moment of triumph of an inquisitive, and maybe wavering, faith. From a narrative point of view, it feels real, and raw, and grieving and surprising in a way that the simple acceptance from the other versions of doesn’t. Thomas, one of the closest allies of Jesus and no doubt a God-fearing man, does not believe immediately. He doubts first. His doubt leads to his testing (by touch) and then to his understanding and acceptance. And though he is somewhat reprimanded by Jesus, Thomas’ doubt is nothing short of brave, even if stubborn. It is also, in its physicality, nasty and potentially painful. While the text is not explicit on whether Thomas does put his finger on the wounds or not, that is the most familiar image that we can imagine of this scene. It is the one that has been represented over and over in art for hundreds of years –an intimate but painful moment of flesh and blood, as much as a moment of astonishment.

Faith and the search for answers

Doubt is a profoundly human feature. We doubt, we question, we try to reach for answers. Moments of doubt, and with it fear, characterize human nature and understanding, and therefore, they characterize faith. Another biblical story that I love is the one where Simon Peter, another of the disciples (arguably the main disciple in Catholic tradition), denies Jesus three times. He repeatedly, over the course of a night says he doesn’t know his friend, teacher, master. Jesus knows this will happen, and in fact he alerts all twelve disciples of it (just as he knows one will betray him), and yet Peter does it and feels shame for it. But fear is stronger. And what is fear if not a type of doubt? In my mind at least, they are inextricably related. Doubt causes fear. The lack of certainty makes us fearful of the unknown. Though Peter was afraid of punishment, and does not doubt Jesus himself, he is still fearful, and it is this fear, this cowardice and failure that I find so compelling and so deeply humanizing about the story. These are the same reasons, though with a different emotion, that I feel in the case of the “doubting Thomas” story.

I like how the 2024 film Conclave puts it ¹. The protagonist, a deacon charged with the task of begrudgingly organizing the new papal election (the Conclave) after the last Pope’s death, kicks off the event by delivering a speech about how doubt is essential to faith. Not only that, but that certainty is the enemy of faith. Wikipedia tells me some clergymen criticized this discourse (that was not meant to be theological anyways) for its characterization of doubt as essential to faith. But honestly? I think every person, whether religious or or not, should embrace doubt as a main aspect of thinking. Critical thinking implies doubt. But doubt is also the beginning of belief, as it was for Thomas. Though religion and spirituality don’t provide the same type of empirical evidence as does modern natural science (such as physics) or produce the same type of “objective” transmissible knowledge and universality of mathematics, it nevertheless produces its own “truths” or certainties for the believer.

Religion seeks to answer some of existence’s great questions (what are we made of? Why are we here? Who are we? Why is there suffering in the world? What happens after we die? Can we ever know The Truth?). In this, like philosophy, it seeks and it provides answers, questionable answers from the outside, but certainties that rule life for those who believe in them. Philosophy has doubt and a type of research right at its core while religion tends to veer towards a specific dogma or dogmas, because religion is not composed just by a spiritual dimension, but also by a communal, social, and political dimension. Religion gives rules. Every great civilization has some religion at its core because it helps provide social structure, divide right and wrong, organize thought around a more or less shared set of beliefs and concepts. In short, it unionized the community while providing distinction from outsiders, therefore it offers a structure of belonging.

In this sense one could argue all religion is organized religion, even if some religions have decided to organize around looser, less dogmatic structures or have given individuals the “power” to read scriptures or “talk” directly to their deity (as did Protestantism in its inception). There are non-theistic religions, set around ancestor worship for example, or animistic religions that center around vastly different concepts from monotheistic religions (the ones we’re most familiar with in the West and Middle East), and that may seem less structured from our point of view. Yet, at least in the case of Christianity, people tend to get together and recreate certain structures of power. For example, while Protestantism, born out of the thesis of Martin Luther in the 16th century denounced the corruption of the Catholic Church and individualized the Christian faith and advocates for a more open interpretation of the message of the Bible, dozens of groups that sprung from it have organized their own structures, interpretations and dogmas, that may be just as rigid as Catholic structure.

One of the many topics that greatly interest me and that I go back to from time to time is that of early Christianity. The historical, cultural, and theological process by which Jesus’ teachings and his group of adepts stopped being a simple subset of Judaism and became a distinct religion, and not only that but also went on to basically “conquer” the Roman Empire. This interest has led me to podcasts, documentaries, and books such as Eve, Adam and the Serpent by Elaine Pagels. The book by itself is quite fascinating, as the author follows the different interpretations of the Genesis story of Adam and Eve and finds in them the “evolution” of ideas that went on to shape the early Christian Church, and how many of the ideas born of this historical process are still present in modern day politics (particularly the idea of “free will” that has then shaped our modern democracies, as well as the idea of “original sin” and how it became doctrine). The book shows that from the very beginning, ideas have been fighting and contraposing one another. People have argued, debated, and questioned themselves, and each other. This debate is what I call “collective doubt”. That is why I argue that doubt, in a collective sense, is present at the birth of every religion. Doubt produces questioning, and questioning produces different thoughts, opinions and dogmas. These might cause divisions and then create different paths for the faithful.

Ultimately, through a complex mix of persuasion and open violence, some ideas prevail over others, such as the agustinian idea of the original sin. When there is no agreement (or some sections can’t be subdued), schisms appear. Different contexts and historical processes produce different systems and debates. For example, the Ethiopian Church has a biblical canon that includes books the Catholic and Orthodox churches consider apocryphal. What all of these schisms and divisions prove is that, one, everything is open to interpretation; two, interpretation appears because we can think critically, and in sum, because we doubt. However, these divisions turn dogmatic and even deadly as some groups are violently suppressed and different denominations and religions kill each other over disagreements.

Science and the pursuit of knowledge

Descartes famously wrote “I think, therefore I am”. I would argue that we need to add “I doubt, therefore I think”. Doubt is powerful, and essential, but it’s also dangerous, at least for those in power. For them, doubt leads to questioning of the status quo, which can’t be accepted. In religion, it is as obvious as in politics. If we have a specific economic system, which someone begins to question, they may come up with ideas which directly confront, and even threaten this system. Doubt is at the heart of every revolution, religious, political, or scientific. First the doubt, then the proposal or fight for alternatives.

Science is crucial to technological advancement and to human understanding. In a lot of ways, there is nothing more human than the pursuit of knowledge for the sake of knowledge. We are curious, resourceful creatures that create technology (from putting two stones together to begin creating a path, to making wheels, creating thread for our clothing and launching satellites). We are also social, political and discursive creatures. The scientific method is, in my opinion, one of the most humanistic pursuits we have ever created. Why? Because both knowledge, an idea of advancement and improvement, and the cruciality of questioning are all at the center of it. The limits of our understanding also show in science, and they become speculative ideas that might create dogmas (though maybe not as potentially deadly as religious dogmas have proven to be). The debates that lie at the heart of the limitations of the Standard Model of particle physics have birthed theories and ideas that are widely discussed, for example.

The scientific method sets consensus by, basically, having a theory “reign” but only as long as there is no better option. In this way, we went from classical mechanics (still used today) to the more fine-tuned quantum mechanics and special relativity to account for the unfathomably small sizes of subatomic particles and the inconceivable velocity of light and distances in space, respectively. Many people have argued, and I agree, that in a sense, science is also a belief that, like religion, requires faith. We can see every day the consequences of the loss of faith in science by looking at the news of antivaxxer and flat earth movements, among others.

There is great spirituality around the questions scientists (like philosophers) ask themselves. The enormity of the universe makes us feel small, even irrelevant, though we are also quite literally made of stardust. Christians, muslims and jews may find themselves lost in the vastness of their God, yet welcomed and loved in the message of their holy scriptures. Similarly, some less religiously inclined people will find themselves desperate by the powerlessness we have in face of nature, by how irrelevant we are individually in the inescapable current of history, in the vastness of the Cosmos while others might find solace in understanding how the forces of nature work, or in their own anonymity. Some will accept the untamability of nature, while others will console themselves with the idea that, despite that, some deity loves them and protects them. In this sense, both secular “atheist” thinking and “religious” thinking are alike, based on interpretation as much as on the faith/confidence that either science, religion or a mix of both, provide the necessary answers to conduct life and live with the inevitable tensions that these questions raise.

Critical thinking and empathy

I think the most important thing modern science and the scientific method has brought us is a framework that has potential to be cross cultural ², cross religious and, in short, as universal as we can humanly get (though of course science has a lot of euro-centrism to be blamed for). The best thing is that this framework is based on critical thinking, one of the most important intellectual skills we need to develop.

With this essay, I want to encourage you to question everything. While I brought up the story of Thomas, I’m not interpreting it in any theological way, but as a parable to prove a point about how we think, and the need to embrace critical thinking in all aspects of our life, spiritually too. It is not a destructive doubt, to constantly shake our mind and spirit, to turn ourselves into rebel without causes, because living also implies trust, which in turn implies faith. We need to believe, believe that we can live our day somewhat peacefully, believe in the institutions that sustain our lives, have faith in science or medicine, etcetera. But beliefs should not be completely inflexible, and doubt should help us review ourselves, our moral codes, the world we live in. As humankind our lack of knowledge and answers is part of the reason why we’re so helpless in the world: our ignorance is like a wound or a hungry beast in our mind that we constantly seek to fill.

If Jesus let Thomas put the finger inside his wound, I’m sure it hurt. But only when we doubt, when we think deeply, even when we are fearful of what we may find, even when it's painful, only then can we reach an understanding (a belief) we are comfortable with. Welcome doubt even when it comes with fear, be willing to be wrong, and recognize you are wrong, because the problem isn’t faith, or even certainty. The real problem is the lack of critical thinking and, just as importantly, dialogue with others. Only with dialogue can we reach mutual agreements and debate without devouring each other.

Empathy begins with understanding, and understanding begins with questioning, the willingness to be ignorant and transform that ignorance and uncertainty into knowledge. In a world that helps us, perhaps needs us, to be stuck in our beliefs (by algorithms that only show us things we agree with, by polarizing the political spectrum, by constantly painting a picture of “us” vs “them”), it is our duty to think and doubt, to find a balance between soothing and questioning, because ignorance begins with not thinking, with shutting down the questions within yourself. To embrace doubt is to be prepared to accept the grey shades of life, the nuances, to be empathetic, to be flexible, and adaptable. Doubt is the seed of growth.