'United' in the Bible

For if we have become united with him in a death like his, we will certainly also be united with him in a resurrection like his.

And they, if they do not go on without faith, will be united to the tree again, because God is able to put them in again.

For if you were cut out of a field olive-tree, and against the natural use were united to a good olive-tree, how much more will these, the natural branches, be united again with the olive-tree which was theirs?

so that you may glorify the God and Father of our Lord Jesus Christ with a united mind and voice.