Peter quotes the text from Psalm 34 in 1 Peter 2:2–3: Like newborn infants, long for the pure spiritual milk, that by it you may grow up into salvation—if indeed you have tasted that the Lord is good.
When the people came to believe in Christ, that was the moment of the great taste of God’s love. They were born again. And they can taste it again when they read the Word of God.
Also see Hebrews 6:4–6. This text speaks about tasting the heavenly gift, tasting the goodness of the Word of God, and tasting the powers of the age to come. That tasting is also about the beginning of faith.
8 Oh, taste and see that the LORD is good! Blessed is the man who takes refuge in him!