Yet, “what we will be has not yet appeared.” We are not like God yet. We are in process; like children in the womb being formed before our birth.
“When [Jesus] appears we shall be like Him.” We will be like Him “because we shall see Him as He is.” We will finally fully know Him.
As Paul says, “For we know in part and we prophesy in part, but when the perfect comes, the partial shall pass away… For now we see in a mirror dimly, but then face to face. Now [we] know in part; then [we] shall know fully, even as [we] have been fully known.” (1 Corinthians 13: 9, 12)
“And everyone who thus hopes in [Jesus] purifies himself as He is pure.” (1 John 3: 3)