The third Person
What spirit do you usually operate in? The simple and tip-of-the-tongue answer for a Christian would be obviously "The Holy Spirit". And that's true. "For in Him we live, and move, and have our being" says Paul to the Athenians (Acts 17:28). But think about the finer expressions of Him that manifest themselves in our day in and day out activities. It's translated from Paul's pen into the King James, rendered as "the spirit of meekness" (1 Corinthians 4:21, Galatians 6:1). It's that spirit of meekness that can be so inviting and appealing to those who don't necessarily want anything to do with the God you know based on the fact that they don't know how He really is. He is so gentle that we as Christians are even liable to overlook Him in spite of knowing where to look for Him. Best not to lose sight of Him in the first place. Elsewhere in writing to the Christians in Ephesus, Paul speaks of "the spirit of wisdom and revelation in the knowledge of Him." (Ephesians 1:17) In the King James, with the exception of the once-repeated story of Jesus walking on the sea to reach the disciples and their mistaking Him for a "spirit" (Matthew 14:26, Mark 6:49), every time you see it, it's the same Greek word (pneuma). It appears hundreds of times in the New Testament. Most times, it's referring to the Holy Spirit, yes. But there are other times where you see this distinction. Where it's almost as if there are other "spirits" at work, and not necessarily bad ones. This might sound heretical but think about it. What happens when you allow the Holy Spirit--of Whom, there's only one--to so infuse with yours, that something fresh and, not new, but original comes of it? Granted, we can only mirror what Christ did for us. And as He had the full measure of the Holy Spirit, any outward act towards another is done from a Christ-like template. But think about it.
The second person
"But all these worketh that one and the selfsame Spirit, dividing to every man severally as He will." (1 Corinthians 12:11)
See, it's the same Holy Spirit who imbues your interactions with others as you seek to please God in the outworking of your faith, as was in and upon Jesus. But your spirit is one of a kind. It's who you are. I have no other personal pronoun to refer to you than a second. If you want to get real semantic, I could say how you're not a body because right there in the structure of grammar and syntax, the "you" is separate from your "body". But the same thing could be said for your "spirit" (your spirit). We are a spirit, no two ways about it. Forgive me for being so forward, but when I say "your spirit", I'm referring to you. The very core of your being, of who you are. As a little side note, maybe the syntax in Heaven, where everything's on a different plane of perfection and the rules are logically different, there are different ways of expressing ourselves. And different ways of expressing about ourselves. Food for thought. I digress. Jesus says "In your patience possess ye your souls." (Luke 21:19) What does this mean? It means we are coalescing into a fuller and fuller version of who God already sees us as. And the closer we get to Him (the Holy Spirit handles the introduction), the more we become that fuller version of us. The more we "possess our souls". It's akin to both full possession by the Holy Spirit and also full self-possession. Keeping one's head, etc.
The First person
How does this work in actuality though? Look at this passage from James: "Who is a wise man (or woman) and endued with knowledge among you? Let him shew out of a good conversation his works with meekness of wisdom. But if ye have bitter envying and strife in your hearts, glory not, and lie not against the truth. This wisdom descendeth not from above, but is earthly, sensual, devilish." (3:13-15)
In other words, be humble and don't try to be something your not on the way to becoming who you are and want to be. I find that I'm satisfied with who I am but I know that God's not finished with me yet. If we never have a horizon on which to train our forward looking, we tend to become complacent. This speaks to the last part of the above passage. We all have moments in our day where common sense seems to be the right answer--the one right answer. The discipline of Jesus, though, is realizing that we have the Holy Spirit who has been given to us to both make us into more and also to bring about the aforementioned illogical solutions to the dreariness of the mundane, day-in-day-out lives we live. I'd rather be thrilled than bored, thank you very much.
In closing, there's a narrative device called "third-person omniscient". Also known as the "God's eye view", it's a way to tell a story or write a novel that allows the narrator (in this case God) to say all that can be said about a situation. Because of what Jesus did for us on the cross of Calvary, we have the Holy Spirit. He is ever present and ready to show what's going on that we wouldn't know or have access to otherwise. From the simple, Christlike attributes of love and meekness and wisdom. To things that you shouldn't know by virtue of logic's strictures, He'll show you what's what. Let Him tell your story.