Jamieson, Fausset and Brown on Philippians 3:20

20. our conversation--rather, "our state" or "country"; our citizenship: our life as citizens. We are but pilgrims on earth; how then should we "mind earthly things?" (Php 3:19; He 11:9, 10, 13-16). Roman citizenship was then highly prized; how much more should the heavenly citizenship (Ac 22:28; compare Lu 10:20)?

is--Greek, "has its existence."

in heaven--Greek, "in the heavens."

look for the Saviour, the Lord Jesus Christ--"We wait for (so the same Greek is translated, Ro 8:19) the Lord Jesus as a (that is, in the capacity of a) Saviour" (He 9:28). That He is "the Lord," now exalted above every name, assures our expectation (Php 2:9-11). Our High Priest is gone up into the Holy of Holies not made with hands, there to atone for us; and as the Israelites stood outside the tabernacle, expecting Aaron's return (compare Lu 1:21), so must we look unto the heavens expecting Christ thence.