Dr. Thomas Manton on Ephesians 4:6, “A Persuasive to Unity in Things Indifferent”:
‘One God and Father of all, who is above all, and through all, and in you all.’ We have one common God and Father, whose eminency is above all creatures, whose presence and powerful providence runneth through all creatures; but his special presence, by the gracious operations of his Holy Spirit, is in the regenerate. Surely this is a strong bond of union, to be one in God. He is the common Father of all believers, through Jesus Christ. Some are weak, some strong, some rich, some poor, but they have all an equal interest in God. Now, for us, who are so many ways one, to be rent in pieces, how sad is that! All these places, and many more, show how every Christian should, as far as it is possible, be an esteemer and promoter of unity among brethren, and not only make conscience of purity, but of unity also, which, next to purity, is the great badge of Christianity.
Source: http://www.puritanboard.com/showthread.php/87866-So-many-ways-one, Comment #1