I was reading in Thomas Watson's "Body of Divinity" and ran across the following paragraph that made me stop and think. I hate to pull something out of a whole chapter of context, but this is considering the scripture- 2Peter 3:18 "But grow in grace"
The general point is that bearing much fruit is growing in grace. I have heard different ideas on the description of what fruit is in the believer's life, but his take is simply 'growing in grace'.
Here is the paragraph I found thought provoking--
"Growth in grace is the beauty of a Christian. The more a child grows, the more it comes to its favour and complexion, and looks more ruddy; so, the more a Christian grows in grace, the more he comes to his spiritual complexion, and looks fairer. Abraham's faith was beautiful when in its infancy, but at last it grew so vigorous and eminent, that God himself was in love with it, and crowned Abraham with this honor, to be the "father of the faithful."
The more we grow in grace, the more glory we bring to God. God's glory is more worth than the salvation of all men's souls. This should be our design, to raise the trophies of God's glory; and how can we do it more, than by growing in grace? " Hereby is my Father glorified, if ye bring forth much fruit." John 15:8
Though the least drachm of grace will bring salvation to us, yet it will not bring so much glory to God. "Filled with the fruits of his righteousness, which are to the praise of his glory." Phil. 1:11 It commends the skill of the husbandman when his plants grow and thrive; it is a praise and honor to God when we thrive in grace."
This last thought is interesting as well...
"The more we grow in grace, the more will God love us. Is it not that which we pray for? The more growth, the more God will love us. The husbandman loves his thriving plants; the thriving Christian is God's chief delight. Christ loves to see the vine flourishing, and the pomegranates budding. Song of Sol. 6:11 He accepts the truth of grace, but commends the growth of grace. " I have not found so great faith, no, not in Israel." Matt. 7:10 Would you be as the beloved disciple that lay in Christ's bosom? Would you have much love from Christ? Labor for much growth let faith florish with good works, and love increase to zeal."