John Calvin on Romans 8:27

27. But he who searches hearts, etc. This is a remarkable reason for strengthening our confidence, that we are heard by God when we pray through his Spirit, for he thoroughly knows our desires, even as the thoughts of his own Spirit. And here must be noticed the suitableness of the word to know; for it intimates that God regards not these emotions of the Spirit as new and strange, or that he rejects them as unreasonable, but that he allows them, and at the same time kindly accepts them, as allowed and approved by him. As then Paul had before testified, that God then aids us when he draws us as it were into his own bosom, so now he adds another consolation, that our prayers, of which he is the director, shall by no means be disappointed. The reason also is immediately added, because he thus conforms us to his own will. It hence follows, that in vain can never be what is agreeable to his will, by which all things are ruled. Let us also hence learn, that what holds the first place in prayer is consent with the will of the Lord, whom our wishes do by no means hold under obligation. If then we would have our prayers to be acceptable to God, we must pray that he may regulate them according to his will.

Romans 8:28-30

28. And we know that all things work together for good to them that love God, to them who are the called according to his purpose.

28. Novimus autem quod iis qui diligunt Deum omnia cooperantur in bonum, iis scilicet qui secundum propositum vocati sunt sancti.

29. For whom he did foreknow, he also did predestinate to be conformed to the image of his Son, that he might be the firstborn among many brethren.

29. Quoniam quos præcognovit etiam præfinivit conformes imaginis Filii sui, ut sit ipse primogenitus inter multos fratres:

30. Moreover whom he did predestinate, them he also called: and whom he called, them he also justified: and whom he justified, them he also glorified.

30. Quos vero præfinivit, eos et vocavit; et quos vocavit, eos etiam justificavit; et quos justificavit, eos etiam glorificavit.