The Divine Word
For he that will love life, and see good days, let him refrain his tongue from evil, and his lips that they speak no guile: Let him eschew evil, and do good; let him seek peace, and ensue it. For the eyes of the Lord are over the righteous, and his ears are open unto their prayers: but the face of the Lord is against them that do evil. And who is he that will harm you, if ye be followers of that which is good? But and if ye suffer for righteousness' sake, happy are ye: and be not afraid of their terror, neither be troubled; But sanctify the Lord God in your hearts: and be ready always to give an answer to every man that asketh you a reason of the hope that is in you with meekness and fear: Having a good conscience; that, whereas they speak evil of you, as of evildoers, they may be ashamed that falsely accuse your good conversation in Christ. (1 Peter 3:10-16 KJVR)


The Human Commentary
We sanctify the Lord God in our hearts when we with sincerity and fervency adore him, when our thoughts of him are awful and reverend, when we rely upon his power, trust to his faithfulness, submit to his wisdom, imitate his holiness, and give him the glory due to his most illustrious perfections. We sanctify God before others when our deportment is such as invites and encourages others to glorify and honour him; both are required, Lev_10:3. "When this principle is laid deeply into your hearts, the next thing, as to men, is to be always ready, that is, able and willing, to give an answer, or make an apology or defence, of the faith you profess, and that to every man that asketh a reason of your hope, what sort of hope you have, or which you suffer such hardships in the world." ~Matthew Henry

For whence is it that we are overwhelmed with fear, and think ourselves lost, when danger is impending, except that we ascribe to mortal man more power to injure us than to God to save us? God promises that he will be the guardian of our salvation; the ungodly, on the other hand, attempt to subvert it. Unless God’s promise sustain us, do we not deal unjustly with him, and in a manner profane him? Then the Prophet teaches us that we ought to think honourably of the Lord of hosts; for how much soever the ungodly may contrive to destroy us, and whatever power they may possess, he alone is more than sufficiently powerful to secure our safety. Peter then adds, in your hearts. For if this conviction takes full possession of our minds, that the help promised by the Lord is sufficient for us, we shall be well fortified to repel all the fears of unbelief. ~ John Calvin