Bible Reading Thoughts: What are the reins?

I will bless the LORD, who has given me counsel: my reins also instruct me in the night seasons. (Psalm 16:7)

I am not sure what this means but the poetic language moves me. Here is Matthew Henry on it:

He repeats the solemn choice he had made of God for his portion and happiness (v. 5), takes to himself the comfort of the choice (v. 6), and gives God the glory of it, v. 7. This is very much the language of a devout and pious soul in its gracious exercises.

...

Making a good use of it. God having given him counsel by his word and Spirit, his own reins also (his own thoughts) instructed him in the night-season; when he was silent and solitary, and retired from the world, then his own conscience (which is called the reins, Jer. 17:10) not only reflected with comfort upon the choice he had made, but instructed or admonished him concerning the duties arising out of this choice, catechized him, and engaged and quickened him to live as one that had God for his portion, by faith to live upon him and to live to him. Those who have God for their portion, and who will be faithful to him, must give their own consciences leave to deal thus faithfully and plainly with them. 

All this may be applied to Christ, who made the Lord his portion and was pleased with that portion, made his Father’s glory his highest end and made it his meat and drink to seek that and to do his will, and delighted to prosecute his undertaking, pursuant to his Father’s counsel, depending upon him to maintain his lot and to carry him through his undertaking. We may also apply it to ourselves in singing it, renewing our choice of God as ours, with a holy complacency and satisfaction.

Henry, M. (1994). Matthew Henry’s commentary on the whole Bible: complete and unabridged in one volume (p. 763). Peabody: Hendrickson.

So, one does their best to adhere to God's statutes, acting in His best interest and according to His will. Where we stumble, we repent. And then in the night seasons, let the conscience percolate, giving space and room to the Spirit to convict, admonish, encourage, or bring things to mind. Is that how you see the verse too?

Night: By EPrata