Today's Gospel reading for Mass is quite short; yawn once and you miss half of it (don't believe me? Check it here). It is short, but pithy. Our Lord does not waste words, even when repeating Himself. The basic thrust is blessing and honour transmits along a chain of interactions, intentionally or not.
The concept is simple. If one honours, blesses, or shows hospitality to someone on a mission, then this person honours, blesses, or shows hospitality to the sender who sent the actual recipient on the mission. Likewise, if the sender likewise is on a mission, then honour is shown by extension to the one upline. Here is the important part: the one who shows honour, blessings, or hospitality receives the same back from the ultimate sender.
This is how we all can partake of the mission God has entrusted to Jesus' disciples. We may be unable to do the work, either by circumstances, health, or anything really, but we can still lend aid where and when we can in whatever measure we are able. We may not be able to be there in the wards visiting the sick, or assisting the homeless or hungry directly, but if we strengthen those who do, provide them resources to perform this, we too are sharing in the work of the Kingdom. In so doing, we share in the honour bestowed on them by God the Father.
The corollary is also true. Honouring, supporting, or blessing the enemies of God, those who seek to oppress or even harm those whom God loved or for whom Christ died (that's everyone, no exceptions) also honour, support, and bless Sin, Death, and Corruption. Where is the blessing in that? How can that bestow honour or life? Sin, Death, and Corruption are nothingness, the Void, a well of non-being and anything thrown that way disappears never to be recovered, and in turn eventually drags the donor in after.
So we all have a choice when a decision is placed before us to give or not to give, to honour or ignore, to bless or to abstain. What decision honours the Gospel? What decision honours the servants of the Gospel? What decision honours God's call for us to look out for each other and therefore honour Him? Those are the decisions we are called to make. All else is truly Nothingness and the Void. Let us choose, and let us choose wisely.