Christ brought the OT to an end NOT by destruction of it but by fulfillment of it There is a difference.
We are not bound by any of the OT law. Therefore adultery is wrong for us today NOT because the OT law says it is wrong but because Christ, His NT says it is wrong. Matthew 5:27-28. Christ went even further than the OT law forbidding not just the physcial act of adultery as the OT law did but condemned lust in the heart as adultery.
Actually it was man that gave the name OT and NT as dividing one from the other, but the Bible is whole from in the beginning in Genesis 1:1 to The grace of our Lord Jesus Christ be with you all. Amen in Rev 22:21. God gave to the Prophets what to speak and write just as God gave to Jesus what to speak, John 12:49, 50.
Jesus taught from the OT including the law. The only laws that Christ has fulfilled so far are that of the Temple and its sacrifices. We are still to follow all the moral laws as we continue to walk in the greatest commandment of love.
Which Old Testament Book Did Jesus Quote From
blog.biblia.com
Jesus quoted from:
Exodus 3:6.............Matthew 22:32; Mark 12:26; Luke 20:37
20:12-16.................Matthew 15:14; 19:18, 19; Mark 7:10; 10:19; Luke 18:20
21:24......................Matthew 5:38
Isaiah 6:9-10.........Matthew 13:14, 15; Mark 4:12; Luke 8:10
56:7.......................Matthew 21:13; Mark 11:17; Luke 19:46
29:13.....................Matthew 15:8, 9; Mark 7:6, 7
5:1.........................Matthew 21:33; Mark 12:1; Luke 20:9
53:12.....................Luke 22:37
54:13.....................John 6:45
61:1, 2...................Matthew 11:5; Luke 4:18, 19; 7:22
Deuteronomy
6:5........................Matthew 22:37; Mark 12:29-33; Luke 10:27
24:1-3...................Matthew 5:31; 19:7; Mark 10:4
19:15....................Matthew 4:4, 7, 10; Luke 4:4, 8, 12
Psalms
82:2; 110:1...........Matthew 21:21:16; 22:44; Mark 12:36; 14:62; Luke 20:42, 43
22:1......................Matthew 27:46; Mark 15:34
31:5......................Luke 23:46
35:19; 69:4..........John 15:25
41:9.....................John 13:18
78:24...................John 6:31
82:6.....................John 10:34
110:1...................Matthew 26:64
118:22, 23...........Matthew 21:42; Mark 12:10; Luke 20:17
118:26.................Matthew 23:39; Luke 13:35
If you go to that website it will give you more greater detail