Genesis 32:2

And when Jacob saw them, he said, This is God's host; and he called the name of that place Mahanaim (double host). He thus commemorated in the name of the place where he was shown this vision the fact that the army of the Lord joined his own little band for the sake of protection. The camp of the angels may have been invisible to all eyes but his own, but he had received his encouragement nevertheless, and went his way with greater cheer.