Consider this, from McLaren's "The Secret Message of Jesus", p. 118.
I should acknowledge that many people assume the sermon (Sermon on the Mount) intends to answer one question--namely, "How does an individual go to heaven after death?"...I have become convinced that Jesus is exploring a very different set of questions--... Rather then directing our attention to life after death in heaven, away from this life and beyond history, these questions return our focus to the here and now--and in so doing, they provide an essential window into Jesus' secret message.
While granting that the Sermon on the Mount is about more than getting to Heaven, the irony comes in when you actually consider some of the things Jesus said in it, which McLaren actually has written out over the next few pages in his book.
Blessed are you when people revile you and persecute you and utter all kind of evil against you falsely on my account. Rejoice and be glad, for your reward is great in heaven...
Therefore, whoever breaks one of the least of these commandments, and teaches others to do the same, will be called least in the kingdom of heaven; but whoever does them and teaches them will be called great in the kingdom of heaven. For I tell you, unless your righteousness exceeds that of the scribes and Pharisess, you will never enter the kingdom of heaven.
pp. 119, 120
These are parts of the Sermon, and are early in the record of it. And we see Jesus telling about the kingdom of heaven and rewards in heaven. Far from being peripheral or even nonexistent, it looks like Jesus' teachings in the Sermon have Heaven pretty much in focus.
Do not store up for yourselves treasures on earth, where moth and rust consume and where thieves break in and steal; but store up for yourselves treasures in heaven, where neither moth nor rust consumes and where thieves do not break in and steal. For where your treasure is, there your heart will be also.
p. 132
This passage gets short changed (pardon the pun) in the book. He tries to make it all about secrecy, which is likely a way of de-emphasizing the "treasures in heaven" aspect--sneaking in treasures on earth, but doing so in a pious and 'spiritual' way; rather, I would say this is about focus. If we keep in mind what the NT says elsewhere about our longing for our real home, where God is, then we can see that storing up treasures in Heaven real is about storing up treasures in Heaven.
To understand McLaren's attempt to de-emphasize Heaven, you must understand that he wants to establish the Kingdom of Heaven here on earth. And I don't mean that he wants Jesus to return to establish His reign on the earth, but that he wants to use political means to establish his version of the Kingdom of Heaven (and if you think I'm misrepresenting him, consider why his writings have such a political element to them, and why he writes for the political blog Sojourners).
Such thinking is wrong. Let him ridicule us as being "escapist" or whatever other labels, as he wishes--he answers no questions that way, and only comes off as childish.