"Blessed are the pure in heart, for they will see God"
If pure in heart means never having a bad thought, I'm unlikely to ever see God! Fortunately that's not what it means. Glen Stassen says pure heartedness is about integrity so that our intentions align with our actions. "Holistically focused" is another one of his phrases. For a number of years, my shorthand for pure in heart has been 'single minded'.
"Seeing God" is also tricky. In Ex 33.20 it says no one can see God and live, yet a few verses earlier (v11) we're told that YHWH used to speak to Moses face to face - like a friend. A kind of comprise happens in the narrative surrounding these verses whereby God passes by Moses, but Moses only sees his back, not his face. However we parse it all out, the bible wants to tell us that seeing God is dangerous, but also transformative. Moses shines with YHWH's glory, which has irradiated him because he 'saw' YHWH on Sinai. In the NT John says "No one has ever seen God but the one and only Son" (John 1.18). Jesus shining at the Mt of Transfiguration is surely significant here too.
So are we meant to understand that Moses and Jesus were specially pure in heart - the shining ones who have seen God?
If so, maybe it was their single minded commitment to God's kingdom which distinguished them. Moses in leading Israel from slavery, interceding for them when they rebel, and bringing them to the cusp of the promise land (read kingdom). Jesus' single mindedness/pure in heart is demonstrable. His mahi is proclaiming God's Kingdom, and even in the garden, facing the cross, it's "your will be done".
Jesus' twin parables of the buried treasure and priceless pearl (Matt 13.44-46) is, I think, all about being pure in heart. Negatively, it's what the rich young rule lacked precisely because he wasn't the sort of person to "sell everything" for the sake of the Kingdom.
So, how do I experiment with being pure in heart this month? I'll write a list. No doubt a long list of ways in I'm not single minded in my pursuit of the Kingdom, and a shorter list of any ways I am more Moses and Jesus-like in my whole-hearted devotion to God's mission. The net result I'll call a doxometer (glory meter). Whether my face shines any brighter or duller.....
Fun fact: A mistranslation in the Latin Vulgate led to many artistic depictions of Moses having horns rather than a shiny face. See here.