The word wisdom (σοφια in Greek) refers to mental and moral insights, prudence and understanding. What this word affirms is that Jesus, who was already well above anything expected of his peers (Luke 2:47 “And all who heard him were amazed at his understanding and his answers.”) continued to develop in wisdom to the point that 18 years later he was ready to accomplish the mission set before him (Luke 3:23 and 4:1).
Stature (ηλικια in Greek) is a word that takes into account a combination of age and size to reflect that physically, Jesus grew in size like any human being would.
Favor (χαρις in Greek and the same word that is translated “grace”) is a term of acceptance. At this point Jesus was being accepted, was favorable to both God and man. However, later he will certainly be accepted by God but rejected by man.
The point of what Luke is telling us about Jesus is that his early life was “normal” in the sense that he experienced everything the rest of us do as we grow up. We learn and grow physically and, hopefully, spiritually. Jesus did too. The writer of Hebrews reflected on it this way, “For we do not have a high priest who is unable to sympathize with our weaknesses, but one who in every respect has been tempted as we are, yet without sin” (Hebrews 4:15 ESV). The same writer also said, “Although he was a son, he learned obedience through what he suffered. And being made perfect, he became the source of eternal salvation to all who obey him” (Hebrews 5:8–9 ESV).
It is interesting that similar things were said of John the Baptist: “And the child grew and became strong in spirit” (Luke 1:80 ESV) and Samuel, “Now the boy Samuel continued to grow both in stature and in favor with the LORD and also with man” (1 Samuel 2:26 ESV).