Give us, O Lord, a steadfast heart, which no unworthy thought can drag downwards; an unconquered heart, which no tribulation can wear out; an upright heart, which no unworthy purpose may tempt aside. Bestow upon us also, O Lord our God, understanding to know thee, diligence to seek thee, wisdom to find thee, and a faithfulness that may finally embrace thee; through Jesus Christ our Lord.
A fragment of the “Concede michi” (“Concede mihi”), an at-least-early-14th-century prayer that may indeed have been composed by St. Thomas. See, for starters, my comments at http://liberlocorumcommunium.blogspot.com/2014/08/concede-michi-concede-mihi.html.
Thanks for this Steve.