With God all things are possible

Ephesians 4 1-6

As a prisoner for the Lord, then, I urge you to live a life worthy of the calling you have recieved. Be completely humble and gentle: be patient bearing with one another in love. Make every effort to keep the unity of the spirit through the bond of peace. There is one body and one spirit-just as you were called to one hope when you were called--one Lord, one faith, one baptism one God and Father of all, who is over all and through all and in all.

The issue of true unity is not a soft or easy option.
Neither does it mean that we don't have any opinion on anything except the Lordship of Christ. It is good to have strong opinions on everything from politics to the Evolution/Creation debate. But even more important than all of these are the two greatest commandments 'Love the Lord with all your heart, soul, mind and strength' and 'Love your neighbour as yourself'. In my opinion the second commandment can be clarified further by a statement in Galatians 6 v 10 'Let us do good to all men especially those that are of the household of faith'. True love involves seeking to love all people including even those who see things differently from us. Most especially it means loving those people who are children of God. If love is easy it probably isn't true love and if unity is always easy it is unlikely to be the kind of unity for which Christ sweated blood - John 17.