Further to a recent post, I really like the purity argument for BR now. Purity can stand in the circle (see the circular structure of the psalm here) with the anointed king in all ages. Also BR is alliterative with B`R in the same verse. So I have retranslated as follows - and rather than the military metaphor, I have used a fire metaphor for the kiss word.
פֶּן-יֶאֱנַף וְתֹאבְדוּ דֶרֶךְ
כִּי-יִבְעַר כִּמְעַט אַפּוֹ
Aflame yourself pure,
lest he face you,
and you perish in the way,
for kindled a little his face.
So how do you enflame yourself in with - purity? You do what 1 John (3:3) advises - all who have this hope purify themselves as he is pure. Method is unspecified - but application of the ointment and spices of the cross strongly recommended.
And if you are Jewish - then rejoice that your Gentile siblings (even kings and peoples) have such a means to share purity and that this psalm (even this psalm!) implies that they too are invited into covenant. And if you read other books - ask yourself what means are at your disposal to achieve joy in self and over turbulence.