Cross reference
2 Peter 3:8
8 But forget not this one thing, beloved, that one day is with the Lord as a thousand years, and a thousand years as one day.
Psalms 90:4
4 For a thousand years in thy sight Are but as yesterday when it is past, And as a watch in the night.
Romans 11:25
25 For I would not, brethren, have you ignorant of this mystery, lest ye be wise in your own conceits, that a hardening in part hath befallen Israel, until the fulness of the Gentiles be come in;