Charles H. Spurgeon on Psalms 50:5

Gather my saints together unto me. There is a double or twofold gathering to Christ. There is a gathering unto Christ by faith, a gathering within the bond of the covenant, a gathering into the family of God, a gathering unto the root of Jesse, standing up for an ensign of the people. "In that day there shall be a root of Jesse, which shall stand for an ensign of the people; to it shall the Gentiles seek; and his rest shall be glorious." Isa 11:10. This is the main end of the gospel, the great work of ministers, the gathering of sinners unto Christ. But then there is a gathering at the general judgment; and this is the fathering that is here spoken of. This gathering is consequential to the other. Christ will gather none to him at the last day but those that are gathered to him by faith here; he will give orders to gather together unto him all these, and none but these, that have taken hold of his covenant.

I would speak of Christ's owning and acknowledging the saints at his second coming. His owning and acknowledging them is imported in his giving these orders: Gather my saints together unto me. ... Now upon this head I mention the things following: —1. Saintship will be the only mark of distinction in that day. There are many marks of distinction now; but these will all cease, and this only will remain. 2. Saintship will then be Christ's badge of honour. Beware of mocking at saintship, or sanctity, holiness and purity; for it is Christ's badge of honour, the garments with which his followers are clothed, and will be the only badge of honour at the great day. 3. Christ will forget and mistake none of the saints. Many of the saints are forgotten here, it is forgotten that such persons were in the world, but Christ will forget and mistake none of them at the great day; he will give forth a list of all his saints, and give orders to gather them all unto him. 4. He will confess, own, and acknowledge them before his Father, and his holy angels. Mt 10:32 Lu 12:8 Re 3:5. They are to go to my Father's house, and they are to go thither in my name, in my right, and at my back; and so it is necessary I should own and acknowledge them before my Father. But what need is there for his owning them before the angels? Answer. They are to be the angel's companions, and so it is necessary he should own them before the angels. This will be like a testimonial for them unto the angels. Lastly. The evidences of his right to and propriety in them, will then be made to appear. Mal 3:17: "And they shall be mine, saith the Lord of hosts, in that day when I make up my jewels." It is too late for persons to become his then; so the meaning is, they shall evidently appear to be mine. James Scot, 1773.