Precepts may instruct, but examples persuade. - Thomas Brooks

Præcepta docent, exempla movent, Precepts may instruct, but examples do persuade.

When Satan attempts to draw you to sin by presenting God as a God all made up of mercy, oh then reply, that though God's general mercy extend to all the works of his hand, yet his special mercy is confined to those who are divinely qualified, to those who love him and keep his commandments, to those who trust in him, that by hope hang upon him, and who fear him; and that you must be such a one here, or else you can never be happy hereafter; you must partake of his special mercy, or else eternally perish in everlasting misery, notwithstanding God's general mercy. (page 44)

God is as just as He is merciful.