Only pure offerings can be offered. Example joyful praise, generous giving (as opposed to stingy and old 2nd hand stuff). And of course a life that trusts in Jesus to make us a pure offering, acceptable to God, rising up to Him, giving Him pleasure.
A life surrendered in trust in Him, believing that He will cause us to be an offering that will be received by the Father, pure and spotless.
Hallelujah!