It’s no coincidence that Thomas the doubter was physically absent from the gathering of apostles at the same time that he was spiritually absent from Jesus through a lack of faith. The catechetical lesson of this Gospel story is that faith and fellowship require one another. The story of these two post-resurrection appearances, including Jesus’ commissioning the apostles to forgive sins, is focused solely on this teaching: absence from fellow believers equates to absence from God.

In today’s Gospel, Jesus said to the apostles, “Whose sins you forgive are forgiven them, and whose sins you retain are retained.” (Jn. 20:23) In order to understand the mission that Jesus gave to his apostles, I’d like you to take a few minutes to reflect on the meaning of the word “sin.” What is your practical definition of this word? When I say a “practical definition,” I mean one that uses specific, experiential descriptors rather than abstract, conceptual characterizations. An abstract definition of an apple, for example, might be as follows: the mature pome fruit of the genus Malus. A specific, experiential definition of an apple might be: a sweet, delicious snack or pie filling.

How would you define “sin,” based on your personal experience? Take a few minutes to think about your recent encounters with sin.

In our society, the commonly accepted definition of sin contains references to one’s spouse’s annoying habits, one’s neighbors’ thoughtless actions, the risk-taking behaviors of automobile drivers, the dishonesty of government officials, and similar types of anti-social acts. It might come as a shock to many people to learn that the “sins” Jesus refers to in this Gospel passage differ from the commonly accepted definition in two fundamental ways.

Firstly, the “sins” that Jesus had in mind are the actions that the Scriptures portray as the most egregious possible offenses that can be committed: breaking faith with God and neighbor. In the Scriptures, the word “sin” encompasses a wide range of undesirable behaviors, including minor peccadilloes and conventional selfishness. The worst sin, however, is none of these. In the Scriptures, the worst sin is the sin of faithlessness; this is the sin that Jesus warned against and the one that he commissioned his apostles to forgive.

Secondly, the “sins” that Jesus called his hearers to repent of were not the sins of other people. A practical description of sin that includes actions like one’s spouse’s annoying habits, one’s neighbors’ thoughtless actions, the risk-taking behaviors of automobile drivers, and the dishonesty of government officials is a definition that ignores the central core of Jesus’ preaching: personal repentance. In the preaching of Jesus, the only sins that deserve one’s attention are one’s own failings rather than the perceived moral failings of others.

The “sins,” then, that Jesus commissioned his apostles and their successors to forgive are not the laundry list of immoralities that are the usual topic of discussion during the Sacrament of Reconciliation. Nor is the purpose of this forgiveness mentioned in the Gospel the usual purpose of going to Confession, namely, to avoid punishment for one’s selfish behavior. The “sins” that Jesus intended his apostles to reconcile were the sins represented by Thomas the doubter: the intertwined sins of estrangement from God and estrangement from neighbor. Not coincidentally, these are also the sins that lead to defining sin in terms of the offensive behavior of others.

Repentance of the sins that Jesus judged to be humanity’s cardinal failings requires a choice as uncommon as Jesus’ definition of sin. In order to repent of the sins that Jesus found most offensive and most deserving of repentance, one must choose first to act responsibly toward God and neighbor. Admittedly, being responsible is considered to be the equivalent of a mortal sin in our culture, but it is also the only way to live according to Jesus’ teachings.

There is only one way to overcome the most egregious sin that results from human weakness. If you, like Thomas, are plagued by doubt, discouragement, or disbelief, the only path to redemption is the one described by Jesus’ definitions of sin and repentance: be reconciled both to God and your neighbor, and do so in the most practical ways possible. Rather than worrying about your personal anxieties, show compassion toward those who struggle and are burdened. Rather than surrounding yourself with comforting things and experiences, bring comfort to those who are sorrowful or deprived. Rather than relying on your own efforts to obtain a satisfying life, pursue God’s will for your energies, attention, and efforts.

If, on the other hand, you have found the redeeming faith preached by Jesus, you have the obligation to be an example of that faith to others. Are there people in your immediate environment who lack faith or who fail in their human relationships? If so, Jesus’ commission to the apostles is addressed to you: be a reconciler, provide the people around you with a practical experience of the faith that focuses more on others than self.