“Beloved, now are we the sons of God, and it doth not yet appear what we shall be: but we know that, when he shall appear, we shall be like him; for we shall see him as he is” (1 John 3:2 KJV).
The most commonly translated Greek words for the word “son” in the New Testament are “huios” and “teknon.”
“Huios” refers to those who are adopted or raised to become like the one who brings them up. Its usage in scripture like Romans 8:14, 19, etc., connotes those raised by God to walk in divinity.
Another way to put it is that the “huios” are those who, by virtue of the proper spiritual training, have come to spiritual maturity—they’re the adopted sons of God.
“Teknon,” on the other hand, means biological offspring; one given birth to through biological means. The reference in the scripture above describes the Christian as the biological offspring of God.
This is the same context the word is used in John 1:12-13 (KJV): “But as many as received him, to them gave he power to become the sons (teknon) of God, even to them that believe on his name: which were born, not of blood, nor of the will of the flesh, nor of the will of man, but of God.”
Thus, in its usage, “Teknon” refers to a child, whether male or female. It describes the spiritual reality that the Christian is genuinely and vitally born of God.