In the Orthodox Study Bible, Proverbs 21:3 reads, "to do righteous things and to speak the truth are more pleasing before God than the blood of sacrifices.
Back at this time period when proverbs was written, Jesus had not been born yet. God's people offered animal sacrifices to Him at the time.
From what I get from this verse is God would rather you do the righteous thing first than not to do it and have to ask forgiveness later.
Speak the truth. This is another place in the bible where we are told to speak the truth. If we are leading a Christian life and being the witnesses we are supposed to be for Jesus, we should speak the truth. Telling the truth is the ninth commandment also. Deuteronomy 5:20 reads, "you shall not bear false witness against your neighbor.
Speak the truth today. Glory to God our heavenly Father.
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