William Barclay tended toward universalism; that comes through clearly in the passages that follow. His universalism was of the sort that was taught and accepted by the Eastern Church and still has strong undercurrents in the Orthodox Churches. However, the universalist perspective, the underpinning of hope for all sinners, provides a unique and useful perspective on Philippians, the most hopeful, the most truly joyous of all of Paul's letters. There is in the text an undercurrent of such incredible intensity and joy that it's hard to rephrase it to make it more clear.
From William Barclay's Commentary of Philippians
It made certain that some day, soon or late, every living creature in all the universe, in heaven, in earth and even in hell, would worship him. It is to be carefully noted whence that worship comes. It comes from love. Jesus won the hearts of men, not by blasting them with power, but by showing them a love they could not resist. At the sight of this person who laid his glory by for men and loved them to the extent of dying for them on a cross, men's hearts are melted and their resistance is broken down. When men worship Jesus Christ, they fall at his feet in wondering love. They do not say "I cannot resist a might like that," but, "Love so amazing, so divine, demands my life, my soul, my all." Worship is founded, not on fear, but on love. . . .
Php.2:11 is one of the most important verses in the New Testament. In it we read that the aim of God, is a day when every tongue will confess that Jesus Christ is Lord. These four words were the first creed that the Christian Church ever had. To be a Christian was to confess that Jesus Christ is Lord (compare Rom.10:9). This was a simple creed, yet all-embracing. Perhaps we would do well to go back to it. Later men tried to define more closely what it meant and argued and quarrelled about it, calling each other heretics and fools. But it is still true that if man can say, "For me Jesus Christ is Lord," he is a Christian. If he can say that, he means that for him Jesus Christ is unique and that he is prepared to give him an obedience he is prepared to give no one else. He may not be able to put into words who and what he believes Jesus to be; but, so long as there is in his heart this wondering love and in his life this unquestioning obedience, he is a Christian, because Christianity consists less in the mind's understanding than it does in the heart's love.
Christianity consists less in the mind's understanding that it does in the heart's love. Doctrine will all be blown away when we stand in the presence--the need for understanding will be gone because we will stand in His presence. And who among us really understands any other human being, much less God? Why do we presume to think that we can better understand God and His commandments than we can understand the person whom we are supposed to love, cherish, and help through life?
And, "Worship is founded, not on fear, but on love." Too often we seem to think the two are somehow related. And yet are we not told, "Perfect love driveth out fear." Fear as we understand it apart from such scriptures as "Fear of the Lord is the beginning of wisdom. . ." is a negative predecessor to generally even more negative descendant emotions. Next to anger, I would suggest that the fear is one of the principle fountainheads of sin. Fear tends to drive people to despair and to desperate acts born of unreason.
But Worship is born out of love, not fear. Worship is the perfection of love. The adoration and whole-hearted devotion that is the essence of worship is a perfection of love--love unbounded. And Paul, in Philippians, clearly teaches the loosing of love on the world.