There are many times the words “without yeast” appear in reference to presenting offerings to God. In the New Testament, Jesus warned us about the "yeast" of the Pharisees.
Matt 16:11b-12
But be on your guard against the yeast of the Pharisees and Sadducees."Then they understood that he was not telling them to guard against the yeast used in bread, but against the teaching of the Pharisees and Sadducees.

Notice how many times the words “a pleasing aroma” appear in Scripture, followed every time in this day’s reading by the words, “an offering made to the Lord by fire.” What is the significance of that for us spiritually?
Rom 12:1
Therefore, I urge you, brothers, in view of God's mercy, to offer your bodies as living sacrifices, holy and pleasing to God-- this is your spiritual act of worship.

2 Cor 2:14
But thanks be to God, who always leads us in triumphal procession in Christ and through us spreads everywhere the fragrance of the knowledge of him.
Is this the "pleasing aroma" He expects from us? To spread the knowledge of Him?

The two tablets of the Testimony were inscribed by the finger of God! WOW!