Jesus asks the disciples this same question. The give Him all kinds of answers, a prophet, the Messiah, Son of God, etc. The charm here is that Jesus already knows who He is. He asks the question to see how the disciples understand who He is. There have been signs, the disciples know Him, but some still don’t completely understand.
It’s such an interesting question. There is often a discrepancy in how we see ourselves and how others see us. Recently, I was playing the “fortune teller” game with my friend’s daughter. She had not written any “fortunes” inside the paper, so I asked her to make them up. Her “fortunes” were- You are strong. You will spend time with someone important, etc. If I asked her to describe me, she tells her version of what I am good at. It’s interesting to been seen through a child’s eyes.
I actually agree with her description of me, but I don’t always see myself that way. I don’t always see the positive qualities in myself, but also, other people’s opinions are not true a lot of the time. We grow and change over time and something that might have been true 5 years ago or even 6 months ago, may not be true today. It’s important to see the difference.
Think about it for a moment. Can you imagine how God sees us? What would He say about us? Would that description be the same as how you describe yourself? If your answer is no, ask God to show you how He sees you today. Write it down, and say it every day until you describe yourself that way.