From Leviticus 16-17
Lev 16.1-28 Law; Festival, Day of atonement, for Aaron, his house, his people, the holy place and tent of meeting.
Lev 16.29-34 Law; Festival, Day of atonement, frequency and summary statement
Lev 17.1-9 Law; Temple Worship, Instructions to only sacrifice at the tent of meeting
Lev 17.10-16 Law; Food and drink; Prohibition against drinking or eating blood
Lev 18.1-23 Law; Sexual immorality, Prohibitions against incest, Adultery, Idolatry, sodomy, bestiality
Lev 18.24-30 Law; Sexual immorality, warnings and summary statement
Passage and Comments
The LORD is aware of Israels tendency for adultery. The underlying premise of this passage is that Israel is bonded to the LORD, but remains unfaithful to him. The root issue behind the golden calf again.
[17:1] And the LORD spoke to Moses, saying,  “Speak to Aaron and his sons and to all the people of Israel and say to them, This is the thing that the LORD has commanded.  If any one of the house of Israel kills an ox or a lamb or a goat in the camp, or kills it outside the camp,  and does not bring it to the entrance of the tent of meeting to offer it as a gift to the LORD in front of the tabernacle of the LORD, bloodguilt shall be imputed to that man. He has shed blood, and that man shall be cut off from among his people.
 This is to the end that the people of Israel may bring their sacrifices that they sacrifice in the open field, that they may bring them to the LORD, to the priest at the entrance of the tent of meeting, and sacrifice them as sacrifices of peace offerings to the LORD.  And the priest shall throw the blood on the altar of the LORD at the entrance of the tent of meeting and burn the fat for a pleasing aroma to the LORD.  So they shall no more sacrifice their sacrifices to goat demons, after whom they whore. This shall be a statute forever for them throughout their generations.
 “And you shall say to them, Any one of the house of Israel, or of the strangers who sojourn among them, who offers a burnt offering or sacrifice  and does not bring it to the entrance of the tent of meeting to offer it to the LORD, that man shall be cut off from his people. (Lev 17:1-9)
The inspired authors occasionally use graphic language. The prohibition against sacrificing outside the tent is given an explicit and very graphic reason. They kept on sacrificing to other gods. Israel is idolatrous.
Story of Israel
One of the sad things about Israel is that a fair number of them were not faithful to the LORD. They demonstrate their unbelieving and uncircumcised hearts time and time again. Whenever we see sin in the lives of these people its entirely valid to ask the question, 'Does their lifestyle reflect their faith?'
Story of Jesus
Following the death and resurrection of Jesus is this true also of his followers today? Well depends on the perspective adopted. I would suggest if someone claimed to be a Christian yet remained unrepentant of sin (be it adultery, idolatry, etc) then the question really needs to asked, 'Can that faith save?'
One might in an attempt to curb 'legalism' might say believers keep on sinning so the picture of Israel in the OT is a picture of believers in Jesus today. But does this make sense of 1 Jn 3.5-10 and 1 Cor 5.9-13?Where we see depictions of Israel as idolatrous, we should be reminded of the salvation Jesus will bring in their future.