The Lord Surrounds His People
In the first film of the ‘Lord’s of the Rings’ trilogy, ‘The Fellowship of the Ring’ the scene is brilliantly set. By using a voiceover and showing us images of the Shire (the place where the early part of the story takes place) Peter Jackson, the director and one of the writers, sums up everything we need to know in one line. “Time moves slowly in the Shire, if it moves at all.” In this way, he quickly sets a scene of permanence and security which the book takes many pages to do.
In the same way the Psalmist achieves the same atmosphere in the first part of this psalm. ‘Those who trust in the Lord are like Mount Zion, which cannot be moved, but abides for ever. 
As the mountains surround Jerusalem, so the Lord surrounds his people, from this time forth and for evermore’ (vs1-2). One can imagine the faithful Pilgrims looking at the mountain Jerusalem was built on and thinking of the LORD’S (‘Yahweh’, God’s Covenant name) promises to his people. Apparently, the mountains surrounding Jerusalem hid the city. So the picture is one of protection and security and reminds us of the blessings in the covenant (Deuteronomy 28:1-14) which were promised to the Lord’s people if they were faithful.
Yet verse 3 strikes an ominous note. ‘For the sceptre of wickedness shall not rest on the land allotted to the righteous, least the righteous stretch out their hands to do wrong.’ The Lord may be good to his people, but his people have to be vigilant! It’s possible this Psalm was written at the time of Nehemiah’s reforms. He faced opposition from without (Nehemiah 4) but also from within. Some Israelites were oppressing their fellow countrymen by lending money and charging impossibly high interest so the work of rebuilding the city’s walls was being hindered (Nehemiah 5). Even when the work was completed and the people had been instructed in God’s law and his covenant, after being away, Nehemiah came back to find that God’s law was being broken and the covenant ignored by some of the people (Nehemiah 13:4-31)!
I can’t remember the number of times people have said to me: “that used to be such a good Bible teaching church 20 years ago!” So what’s happened? Did a bunch of heretics suddenly take over its leadership overnight? Of course not! If that happened the faithful would notice! Rather, the teaching of the gospel had been slowly eroded, until one morning the faithful woke up and realise they’re part of a church where the gospel has been lost! The sad thing is: ‘the righteous’ end up being part of a corrupted church! So the Psalmist, being a realist, calls on the Lord’s people to be vigilant and guard the truth. The most chilling words in the New Testament are found in 1 Corinthians 10:1-6. Here Paul 
reminds the Corinthian church of the immense blessing that the Israelites experience during the exodus, yet concludes: ‘Nevertheless, God was not pleased with most of them; their bodies were scattered in the wilderness’ (1 Corinthians 10:5 NIV) as a warning to a proud church!
But the Psalmist takes nothing for granted. The blessings of the first part at Deuteronomy 28 are followed by a series of curses (vs15-68) warning the people what will happen if they fail to keep their part of the covenant! So the Psalmist prays for, and doesn’t take for granted, the Lord’s blessing to the faithful. He prays for protection from those who would try to infiltrate the Lord’s people with bad ideas and he prays for peace (vs4-5). As God’s people had to then, the church today must guard against false teaching. Maybe we’ve been privileged with good gospel teaching over the years. If so, let’s thank the Lord and be humble enough to ask for his continual protection!
Like to hear a sermon on this Psalm? The Lord Surrounds His People!