I have rejoiced ... - I do rejoice; I exult in this; I find my happiness there. The word expresses a high degree of joy.

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With my lips I have declared all the judgments of your mouth.

I have rejoiced in the way of your testimonies
The way which the Scriptures, that testify of God and Christ, direct …

To original corruption all have added actual sin. The ruin of the young is either living by no rule at all, or choosing false rules: let them walk …