God will gather still others to them besides those already gathered and our actions

Isaiah 56:1-12
This is what the Lord says: "Maintain justice and do what is right, for my salvation is close at hand and my righteousness will soon be revealed. Blessed is the one who does this - the person who holds it fast, who keeps the Sabbath without desecrating(褻瀆) it, and keeps their hands from doing any evil.
To eunuch: To eunuchs who keep my Sabbaths, who choose what pleases me and hold fast to my covenant - to them I will give within my temple and its walls a memorial and a name better than sons and daughters; I will give them an everlasting name that will endure forever.
Foreigners who bind themselves to the Lord to minister to him, to love the name of the Lord, and to be his servants, all who keep the Sabbath without desecrating it and who hold fast to my covenant - these I will bring to my holy mountain and give them joy in my house of prayer.
I will gather still others to them besides those already gathered.
In these chapter we return to a restored Jerusalem, and life back home, after the exile. Scenes of sin and failure mingle with scenes of future glory.
V1-8: For all the nations. There is nothing exclusive about the love of God. There is a place among his people for all who will follow and obey him, even the most despised. God's own Temple is meant to be a house of prayer for all the nations.
9-12 : From the ideal we come down to a far different reality. Spiritual and secular leaders alike have gone soft and failed in their jobs.
Why?
God's love is come to all nations and all human beings. Not only Israelite but foreigners who bind themselves to the Lord to minister to him. God's blessing will come upon them.
Even eunuch with despair may have joy and have everlasting name.
Actions are 1) Bind themselves to the Lord to minister to him 2) love the name of the Lord 3) to be his servants 4) keep the Sabbath without desecrating it 5) hold fast to God's covenant 6) keep their hands from doing any evil.
Church is a house of prayer for all the nations.
How?
God's own temple is meant to be a house of prayer for all the nations. Follow the way of God's instructions, bind myself to the Lord to minister to Him.