If incarnation is central to the Good News of Jesus, then the act of eating is central to incarnation. Scan the text for mentions of eating, drinking, and even feasting, and the numerous occurrences of these vocabulary leave no doubt that these actions are important.
Eating is, in the text, more than merely obtaining the calories and nutrients necessary to sustain life. People eating together reflects the notion of building unity and fellowship, as Paul writes in his letter to the Ephesians:
He also gave apostles, prophets, missionaries, as well as pastors and teachers as gifts to his church. Their purpose is to prepare God’s people to serve and to build up the body of Christ. This is to continue until all of us are united in our faith and in our knowledge about God’s Son, until we become mature, until we measure up to Christ, who is the standard.
Notice that the process of unification is exactly that: a process. Perfect unity is a future goal, not a present reality. People who follow Jesus are in a process of continuous engagement. Over time, that engagement moves, perhaps asymptotically, toward agreement.
Incarnation is the glorious promise that we are in motion toward agreement and unity. Incarnation is also the realistic understanding that we, as fallen human beings, will not achieve total or perfect unity or agreement in this life.
Dining together with those who follow Jesus is a “foretaste of the feast to come.” Sharing meals with unbelievers and heretics is an imitatio dei, inasmuch as Jesus often ate with those who were skeptical of His claims to divinity and of His claims to be the Savior of all people.
In the book of Luke, Jesus gives instructions to His followers: to eat with those who “welcome” or “accept” them. They are not to wait to find those who agree perfectly with them, or are in perfect unity with them. A mere willingness to hear the Gospel suffices.
Stay with the family that accepts you. Eat and drink whatever they offer you. After all, the worker deserves his pay. Do not move around from one house to another. When ever you go into a city and the people welcome you, eat whatever they serve you.
Interestingly, Paul also writes (I Corinthians 5:10-11) that circumstances might arise when it would be necessary to reduce the amount of fellowship one might have with certain people. This passage requires careful analysis. Paul tells us that we should not “associate” with certain people, but adds that we should continue to “have contact with” them.
Who are these people with whom we should not “associate”? Because all people sin, it cannot be that we should break fellowship with anyone who sins. Paul notes that it would be impossible to break off fellowship with sinners, and even if it were possible, it wouldn't be desirable. Rather, fellowship should be reduced, but not entirely cut off, with those who fail to acknowledge themselves to be sinners.
Jesus is interested, after all, in sinners. Jesus “welcomes sinners and eats with them” (Luke 15:2).
If there is anyone with whom we should not eat, then, it is those who consider themselves to be without sin, who consider themselves to be perfect. To be sure, there are many who would never proclaim themselves to be perfect, but whose actions and words imply some attitude of self-righteousness.
But rather than worrying about our supper companions, it is much more relevant that we direct this warning to ourselves: do we “examine ourselves” (II Corinthians 13:5)? Are we willing to admit that we are sinners? To admit that we sin? To admit that we are sinful?
Let us be unambiguous with ourselves about who and what we are. When we confess that we are sinners, that we are sinful, and that we sin, - then we can be certain of God’s compassion and love toward us.