Summary: There is no question that Jesus taught on the foreknowledge and election of the Father. We trace this teaching now throughout the history books of the New Testament.
Fittingly in the New Testament, our first encounter with God's sovereignty is in regards to Jesus Himself. 1:21 gives us the words of the angel that His name will be Jesus. A small point, you say. Yet, here God intervenes in the process of childbirth and imposes His own will on a mother. Yes, the child is His own, but some object to God's intervening in any way among us. Give us our free will. We will name our children. We will guide them into their careers. We'll be their protectors.
Sovereignty teaches that it is God, and not man, Who makes all these decisions, using His gentle Spirit's proddings and speakings to make it happen.
Jesus is born, grows, and takes on His ministry of teaching. Towards the end of the famed lesson on the hillside,7:23, He surely startles his audience when He informs them that persons who seem to be ministering with the power of Heaven will be ejected from the Kingdom when Jesus declares He never knew them. This seems to compare favorably to Hebrews 6:4-8, where persons who came very close to the power of God and son-ship actually fall away and are refused.
The verses are important to our study in showing us that true believers will persevere, but those who only have the external trappings of salvation will not. In both passages, they are refused, and we are told that the requirement for salvation is Jesus' intimate knowledge of them, implying eternal selection. See also John 10:14, where Jesus says that He knows His sheep, and is known by them. Relationship.
I enjoy finding what I call "Rosetta Stones" when searching out doctrines. In this case, a Rosetta Stone verse would be one that seems to be on both sides of the Sovereign Grace issue. Such a passage is 11:25-28.
The narrative is of a prayer to God and a plea to man. We see the very mind of God in the prayer, but the method for evangelism in the plea. It is most instructive.
The prayer. "You have hidden these things [that I am teaching publicly ] from the wise and prudent and have revealed them to babes..." He explains further that "no one knows the Son except the Father, nor does anyone know the Father, except the Son, and he to whom the Son wills to reveal Him."
Oh my, shut the book! What further evidence do we need of the heart of God and His Son? Together, Father and Son make known to specific, pre-ordained men and women the revelation of Who Jesus is, of what salvation is all about, forgiveness of sins, eternal life. That is how we know God and God knows us.
I am so glad that Jesus abruptly stopped that chain of thought, turned to the audience, and said, "Come to Me, all..."
His method was and continues to be "Whosoever will may come." His theology, and ours, must be, "No one, except the ones to whom the Son wills to reveal Him."
It's not either or. We must evangelize believing everyone who hears us is called to salvation. We must rejoice that the one or two or more that come along with us have been called by the Father.
There's a tension there, a balance we must achieve in our thinking. But both truths are real.