“For if these things be in you, and abound, they make you that ye shall neither be barren nor unfruitful in the knowledge of our Lord Jesus Christ.”  
2 Peter 1:8

“And beside this, giving all diligence, add to your faith virtue; and to virtue knowledge; And to knowledge temperance; and to temperance patience; and to patience godliness; And to godliness brotherly kindness; and to brotherly kindness charity.” 2 Peter 1:5-7
He admonishes us to be diligent; be diligent about your participation in the faith, don’t just sit around expecting moral excellence to appear as you work your faith, he says giving all diligence add virtue to your faith!
Faith is great, but to be consistently active and productive, you have to add virtue, and to that virtue, add knowledge!
Be diligent about gaining knowledge, he says your knowledge should abound, so knowing something would affect the manner with which you live out your divine life and the kind of results you produce.
The word knowledge is gotten from the Greek- gnosis; which means, knowledge gotten through scientific study. This is different from revelation knowledge, you have to study to gain this kind of knowledge, so God wants you to be a diligent student of the word; it’s one thing to meditate on one verse, it’s another thing to diligently study the Bible as a student, he says- those who choose to be schooled in and by the word would definitely be more active and productive Christians.
“Study to shew thyself approved unto God, a workman that needeth not to be ashamed, rightly dividing the word of truth.”  2 Timothy 2:15