Do we mention the cross in our homilies and sermons? The Apostle more than mentioned it:
When I came to you, brothers and sisters, I did not come proclaiming the mystery of God to you in lofty words or wisdom. For I decided to know nothing among you except Jesus Christ, and him crucified. And I came to you in weakness and in fear and in much trembling. My speech and my proclamation were not with plausible words of wisdom, but with a demonstration of the Spirit and of power, so that your faith might rest not on human wisdom but on the power of God. (1 Corinthians 1:2-5)
Where is the one who is wise? Where is the scribe? Where is the debater of this age? Has not God made foolish the wisdom of the world? For since, in the wisdom of God, the world did not know God through wisdom, God decided, through the foolishness of our proclamation, to save those who believe. For Jews demand signs and Greeks desire wisdom, but we proclaim Christ crucified, a stumbling block to Jews and foolishness to Gentiles, but to those who are the called, both Jews and Greeks, Christ the power of God and the wisdom of God. For God’s foolishness is wiser than human wisdom, and God’s weakness is stronger than human strength.
Consider your own call, brothers and sisters: not many of you were wise by human standards, not many were powerful, not many were of noble birth. But God chose what is foolish in the world to shame the wise; God chose what is weak in the world to shame the strong; God chose what is low and despised in the world, things that are not, to reduce to nothing things that are, so that no one might boast in the presence of God. He is the source of your life in Christ Jesus, who became for us wisdom from God, and righteousness and sanctification and redemption, in order that, as it is written, “Let the one who boasts, boast in the Lord.” (1 Corinthians 1:20-31)