Luke 1:3 It seemed good to me also, having had perfect understanding of all things from the very first, to write unto thee in order, most excellent Theophilus,

This is the only time in the KJV bible that these two words are put together, perfect understanding. Let me expand on the “all things” for a moment and remind ourselves that the “all things” comment refers to what Luke says in verse 1, “those things which are most surely believed among us”. It is not in all things but refers specifically about those things which were in common belief about the events surrounding the birth, life, death and resurrection of Jesus Christ. Nothing else is in question as to what is contained in all things.

John 4:25 The woman saith unto him, I know that Messias cometh, which is called Christ: when he is come, he will tell us all things.

Here the Samaritan woman expresses her understanding of the coming Messiah’s ability to express all things, but is her understanding correct?

John 5:20 For the Father loveth the Son, and sheweth him all things that himself doeth: and he will shew him greater works than these, that ye may marvel.

Here Jesus expresses a perfect understanding of what the Father is doing in that moment with the purpose of glorifying the Father. All things are limited to an event or events as revealed.

John 14:26 But the Comforter, which is the Holy Ghost, whom the Father will send in my name, he shall teach you all things, and bring all things to your remembrance, whatsoever I have said unto you.

Here all things is inclusive only of those things which Jesus said and wants repeated, not everything under the sun.

1 Corinthians 13:9-10 For we know in part, and we prophesy in part. But when that which is perfect is come, then that which is in part shall be done away.

So then when perfection comes, that which we knew in part, we shall no longer know.

We know nothing as we should know it. (1 Corinthians 8:2)