From Mark Booker
Psalm 135: The biblical critique of idolatry is found here in words nearly identical to Psalm 115. YHWH is great (v5) and can do whatever he pleases (v6). He is to be praised and blessed. The idols, who are merely the work of human hands, can't speak, see, hear, or breath (vv15-17).
At the heart of this psalm is the promise that "YHWH will vindicate his people and have compassion on his servants" (v14). There is great comfort in this promise, a promise that is illustrated most clearly in the resurrection of Jesus.
Psalm 136: The steadfast love of YHWH - his radical commitment to his covenant partner Israel - endures forever. The psalm recounts the acts of that steadfast love in creation and redemption. To doubting hearts, this psalm is a wonderful salve.
1 Corinthians 5.1-13: Paul chides the Corinthian community for their lack of discernment. A man is living in sexual immorality and they're not concerned. They've failed to exercise discernment and right judgment. Paul calls upon the church to remove this man from their community and quotes a repeated refrain from Deuteronomy, "Purge the evil person from among you."
We heard last Sunday about the need for discernment when it comes to false teachers/prophets. That same discernment is needed to rightly judge those inside the church (v12) - yes, we are called to exercise judgment in this case, with those inside (not outside) the church. The drastic step of removing someone from the community is rare (though note that Jesus teaches something similar in Matthew 18), but it is biblically endorsed as an act of love that is aimed at leading the one living in willful, unrepentant sin to repentance, "that his spirit may be saved in the day of the Lord" (v5). Hard as this is to comprehend, expulsion is a loving act aimed ultimately at restoration. It drives home the consequences of sin to someone who is otherwise unwilling to acknowledge them.
The concern for the individual is paired with a concern for the holiness of the Christian community. Sin is a big deal and it has an impact upon the whole. The Christian community can't just look the other way. Those who embrace sin willfully and without repentance put their standing in the community in jeopardy because the holiness of the community matters.