Exodus 32:15
And Moses turned, and went down from the mount, and the two tables of the testimony were in his hand: the tables were written on both their sides; on the one side and on the other were they written.
Cross-reference
Exodus 24:18 sets the context — Moses was on the mountain forty days before descending with the tablets.
Exodus 24:12 records God's command to Moses to come up and receive the stone tablets written by God — the same tablets Moses carries down in 32:15.
Exodus 31:18 describes the giving of the two tablets written by God's finger — the same tablets Moses holds in 32:15 as he descends.
Exodus 25:16 instructs that the testimony (the tablets) be placed in the ark — the same tablets Moses just received.
Exodus 34:29 shows Moses again descending with tablets, but these are the second set after the first were broken — mirroring the earlier descent.
Exodus 40:20 describes placing the tablets inside the ark, a later step in the same narrative sequence.
Deuteronomy 9:15 repeats the same scene — Moses coming down from Sinai with the two tablets.
In 2 Corinthians 3:7, Paul calls the tablets 'ministry of death' — showing the law's condemning power despite its glory.
Deuteronomy 10:5 records Moses placing the tablets in the ark — the same tablets he carried down in Exodus 32:15.
Psalm 19:7 extols the law/testimony written on the tablets — the same 'testimony' Moses carried down, as perfect and reviving.
2 Chronicles 5:10 confirms that only the two tablets Moses placed in the ark were inside — the same tablets from Sinai.