Father.

Luke 15:18, 19
I will get up and go back to my father and say to him, "Father, I have sinned against heaven and against you. . . .

Jeremiah 3:13
Only acknowledge your guilt, that you have rebelled against the LORD your God. You have scattered your favors to foreign gods under every green tree and have not obeyed My voice, '" declares the LORD.

Ezekiel 16:63
so that when I make atonement for all you have done, you will remember and be ashamed, and never open your mouth again because of your disgrace, declares the Lord GOD.'"

Romans 2:4
Or do you disregard the riches of His kindness, tolerance, and patience, not realizing that God's kindness leads you to repentance?

against.

Psalm 51:4
Against You, You only, have I sinned and done what is evil in Your sight, so that You may be found just when You speak and blameless when You judge.

Psalm 143:2
Do not bring Your servant into judgment, for no one alive is righteous before You.

1 Corinthians 8:12
By sinning against your brothers in this way and wounding their weak conscience, you sin against Christ.