John Trapp on Psalms 125:4

Verſ. 4 Do good, O Lord, unto thoſe that be good] But afflicted by thoſe men of thy hand, Pſal. 17.14. who are the rod in thine hand, Iſa. 10.5. Do good in thy good ple[illegible: 1 letter]ſure (for nothing can bee claimed by the very beſt) to ſuch, according to thy promiſe, verſ. 3. which here I put in ſute for them; Let the Lord bee with the good, 2 Chron. 19 11.

And to them that are upright in their hearts] For ſuch only are good indeed, and approved in Chriſt, as was Appelles, Rom. 16 and Nathaniel, Joh. 1. notwithſtanding their infirmities. Hypocriſy imbaſeth the pureſt metal, turneth gold into ruſty Iron; ſincerity doth the contrary by a divine kind of Alchymy.