I haven't forgotten my “eis” when it should’ve read “estin”
:)
Here, my friend, "εις", insofar as you were quoting +Luke, would have been just fine, as in "...εἰς τὴν ἐμὴν ἀνάμνησιν". It means "in". "Εστι", or "εστιν", means "is". But you are doing good. Keep it up. If, by the grace of God, you gain a working knowledge of Greek, it will open a whole world of scriptural understanding for you, which, aside from the spiritual benefits, will allow you to astonish your friends and confound your enemies!