The ‘gem’ is in the promise that ends the letter following the words ‘to the one who is victorious’. Here is the rest of the letter : To the angel of the church in Pergamum write: These are the words of him who has the sharp, double-edged sword. 13 I know where you live—where Satan has his throne. Yet you remain true to my name. You did not renounce your faith in me, not even in the days of Antipas, my faithful witness, who was put to death in your city—where Satan lives. 14 Nevertheless, I have a few things against you: There are some among you who hold to the teaching of Balaam, who taught Balak to entice the Israelites to sin so that they ate food sacrificed to idols and committed sexual immorality.15 Likewise, you also have those who hold to the teaching of the Nicolaitans.16 Repent therefore! Otherwise, I will soon come to you and will fight against them with the sword of my mouth. 17 Whoever has ears, let them hear what the Spirit says to the churches. To the one who is victorious, I will give some of the hidden manna. I will also give that person a white stone with a new name written on it, known only to the one who receives it.
This letter to Pergamum is full of puzzles. We do not know what the things said about the church actually refer to, nor do we know quite what the gifts for those who were victorious mean. However it would be a pity to do only 6 gems for the 7 churches - so here goes!
Pergamum was a considerable city with more than 120,000 inhabitants. It had a vigorous and prosperous life so there will have been a great many small firms giving an active but somewhat chaotic life to it. This seems to have been reflected in the church. We do not know exactly what the imitation of Balaam implied - he seems to be vilified in the New Testament for what he did when the Israelites were in the plains of Moab although the Old Testament account scarcely seems to merit such ill favour. What the Nicolaitans taught we do not know. We can conclude that the church was a bit of a mess with several factions teaching things that were quite wrong.
Yet, even so the church had remained faithful through persecution severe enough to lead to the martyrdom of at least one man, It is probable that the main problem the church members faced when not being actively persecuted would arise from the need for those involved in the main trades to belong to the appropriate guilds. There will have been a Baker’s guild, a Butcher’s guild, a Tent Maker’s guild etc. The problem these caused members of the church was that they would hold regular social meetings, which members would be obliged to attend, at which there would be much feasting, much eating of food offered up at the idol temples, much drinking and much revelry often of a sexual nature. The big and contentious question was how Christian were to cope with all that. They were the same sort of problems that caused so much trouble in the church in Corinth and indeed in the churches all round the Roman/Greek world but seem to have been particularly acute in Pergamum since it is said to be ‘where Satan has his throne’ (Revelation 2:13).
Jesus told the members of the church to repent else he would ‘fight against them with the sword of my mouth’ strongly suggesting that things were very wrong and it is words and argument that are needed to put things straight.
As a result of all their difficulties and struggles the promised gifts for the victorious are ‘hidden manna’ and ‘white stones with a new name written on it, known only to the one who receives it’. Both those are puzzling. The best guesses seem to be: first, that the hidden manna is a reference back to the journey of Israel through the wilderness when they ran out of food. The people of the church in Pergamum will receive something, still hidden, which will encourage and sustain them for their onward journeys of faith. Second, the white stones are an even greater mystery, particularly in the matter of whose name is on them. Pergamum was built on a very dark, almost black, rock and white stone tablets were used for inscriptions. Was the name the very special name of Jesus “ that no one knows but he himself” mentioned in Revelation 19:12 etc.?, It is possible. Or was it the new name that was to be given to every disciple to fulfil the prophecies of Isaiah 62:2 (“The nations will see your vindication, and all kings your glory; you will be called by a new name that the mouth of the LORD will bestow”). This latter would seem the most likely. They would be given a new name signifying a new start in life and a new relationship with the Lord.
The problem of fitting into the culture we are in and in which we have to live is very real for us all. The promises of new spiritual food and a new relationship with the Lord are wonderful promises for us all. So despite the puzzles of Pergamum there are good and rich things to be learnt here.