Charles Spurgeon Commentary 2 Peter 1:5

"Yea, and for this very cause adding on your part all diligence, in your faith supply virtue; and in [your] virtue knowledge;" — 2 Peter 1:5 (ASV)

Giving all diligence,

It is not man's effort that saves him; but, on the other hand, grace saves no one to make him like a log of wood or a block of stone; grace makes man active. God has been diligently at work with you; now you must diligently work together with him.

And beside this, giving all diligence,

For we cannot expect to go to heaven asleep. We are not taken there against our wills. It is not our will that accomplishes our salvation; but still, it is not accomplished without our will. "Giving diligence," yes, but more than that, "giving all diligence."