1 Peter 2:3
If so be ye have tasted that the Lord is gracious.
Cross-reference
Hebrews 6:5
Parallel
In Hebrews 6:5, the same 'tasted' metaphor applies to the word of God and powers of the coming age, echoing the experience of the Lord's goodness.
Psalm 34:8
Citation
Psalm 34:8 is the direct source: 'Taste and see that the Lord is good'—Peter quotes this to ground his encouragement.