Jesus answered and said to him, Art thou the teacher of Israel, and perceivest thou not these things? The term "Israel" is used four times by John (John 1:31, John 1:49; John 12:13; and here). In each place the high dignity, calling, and glory of the nation chosen for the loftiest privilege and destiny are involved.
Notice the article, "the Israel" of God. The article before διδάσκαλος gives a high distinction to Nicodemus. Schottgen and Lucke suppose some special office to be here referred to, either the president of the Sanhedrin, or the hakim, or chakam, "the wise man," who sat on his left in the public sessions, or the "father of the house of judgment," who sat on his right; but it may simply mean the teacher of Israel, who has come to me in representative fashion, and who is reminded that he should have been more intimately acquainted with the teaching of his own sacred books.
Without doubt, the fact of human corruption, and the power of the Spirit of God to renovate, to change utterly down to the very core and heart of human nature, is a great dogma of the Old Testament (cf.
Deuteronomy 10:16; Deuteronomy 30:6; 1 Samuel 10:9, where God gave Saul another heart; 1 Samuel 16:13, the effect upon David; David's own prayer, Psalms 51:10; and the great promises of God by Ezekiel, Ezekiel 11:19; Ezekiel 18:31; Ezekiel 36:26; Jeremiah 4:4; Jeremiah 31:33).
Nicodemus, an illustrious man, a teacher of ethers, presumably acquainted with the teaching of the Scriptures, need not have been in such doubt and amazement at the searching words of Jesus.