This little poem comes from Disticha de Educatione of Urbano Appendini, published in 1834; you can see the whole book at Google Books.
Non nostra in terris sedes: caelum aspice: regna
Nos illic, obita morte, beata manent.
obeo -īre, obīvī, obitum - to go to meet, go down, perish
aspicio -ere -spēxī -spectum: look to or at, behold
beatus -a -um: happy, blessed, prosperous, fortunate
caelum -ī n.: sky, heavens
illīc at that place, there; illinc, from that place
in: in, on (+ abl.); into onto (+ acc)
maneo -ēre mānsī mānsum: remain
mors mortis f.: death
nōn: not
nōs, nostrum/nostrī nobis nōs: we
noster nostra nostrum: our
rēgnum -ī n.: kingship, kingdom
sēdēs -is m.: seat, abode, habitation
terra -ae f.: land