Confundar is ambiguous, isn't it? It is both future and present subjunctive, so it can mean either I will not be let down or may I never be let down or both.In more accurate and modern English: 'In you, Lord, I have rested my hopes: do not for ever let me down'.
Now you got me interested. The Septuagint psalm 30 uses the optative of the aorist passive:Hmm. The hymn is not totally unbiblical; the quoted lines come from Psalm 31, verse 1. (Some confusion as to numbering exists--it seems to be Psalm 30 in Hebrew, due to the joining of Psalms 9 and 10 into one.) So, if one who knows looks at the Greek and/or the Hebrew, might not this confusion (ha) with confundar be settled?
ἐπὶ σοί κύριε ἤλπισα μὴ καταισχυνθείην εἰς τὸν αἰῶνα |