28 Then Peter spoke up, “We have left everything to follow you!”29 “Truly I tell you,” Jesus replied, “no one who has left home or brothers or sisters or mother or father or children or fields for me and the gospel 30 will fail to receive a hundred times as much in this present age: homes, brothers, sisters, mothers, children and fields—along with persecutions—and in the age to come eternal life. 31 But many who are first will be last, and the last first.”
Ouch. First, you're supposed to leave your wife and family to fend for themselves to follow this guy, and then you're going to "trade up" as it were in kingdom come. Perhaps this is why there is so little shame in having a new "trophy wife" today among so many politicians who confess their allegiance to various charismatic groups.
What's interesting is that just 18 passages before this, Jesus makes the act of leaving your wife out as the one sin that might be seen as unforgivable (Mark 10:6-12. Oddly, this is the passage most often cited as objecting to homosexual activity and same sex marriage-but again, that's for another post at another time.)
This is one of those little gems that is almost word-for-word copied in Luke (18:28) and Matthew (19:27) so scholars tend to give it a lot of weight in terms of likelihood of having been a real exchange. In any case, it appears that to Jesus the sanctity of marriage is violable under some circumstances-namely, that you use following Jesus as an excuse for it. Conceivably, that means it would be perfectly acceptable to join a monastery or become an itinerant preacher if one got tired of providing for one's family.