2 Chronicles 35:1
Moreover Josiah kept a passover unto the Lord in Jerusalem: and they killed the passover on the fourteenth day of the first month.
Cross-reference
2 Chronicles 30:1-27 records Hezekiah's Passover, which Josiah's later observance parallels but with correct timing.
Exodus 12:6 instituted the Passover on the 14th day at twilight, which Josiah faithfully observed.
Numbers 9:3 reiterates the Passover timing on the 14th day, followed exactly in Josiah's celebration.
Deuteronomy 16:1-8 provides the law for Passover observance, which Josiah's actions fulfill.
2 Kings 23:21-23 is the parallel account of Josiah's Passover, noting its uniqueness since the days of the judges.
Ezekiel 45:21 prescribes the same Passover date (14th of first month) as Josiah kept here.
Numbers 9:2 records God's original Passover command to Moses, which Josiah's observance follows.
Ezra 6:19 describes a later Passover kept after the exile, echoing Josiah's faithful observance.