Paul begins these verses with a reference to our “God and Father himself, and our Lord Jesus Christ”. Paul wants God himself to be at work. Why?
So that the love of these people for each other might abound! It is hard to make yourself be more loving. There are things we can do, for sure, but when God himself begins to move upon us, then our love can really grow!
And why is it important that our love grow to an abounding level? Paul says that this will enable us to be established blameless, in holiness before the Lord when Jesus comes back. Does becoming more love really makes us more holy? Indeed it does, when we remember that the basis of every commandment is to love God with all our hearts, and love our neighbor as ourselves.
So, ask God himself and Jesus to be at work in you, helping you to be more loving towards God and people and you will find that the second coming of Jesus will be a day of joy and victory!