Where are you resident?

You will guard him and keep him in perfect and constant peace whose mind [both its inclination and its character] is stayed on You, because he commits himself to You, leans on You, and hopes confidently in You. So trust in the Lord (commit yourself to Him, lean on Him, hope confidently in Him) forever; for the Lord God is an everlasting Rock [the Rock of Ages]. Isaiah 26:3‭-‬4 AMPC

Few Lessons:
1. God does the guarding and the keeping, while we are expected to do the staying, the committing, the leaning, the hoping and the trusting. This picture is one of absolute assurance of your own limitation and the confidence that God is able to do all he has promised. If you have options, God also has staying power. He can wait, after all, he has been existing long before this earth was created, and he will continue to exist long after this present world ends. You don't have that luxury, so your options are truly limited.
2. In trusting God, what seems to be key is that your mind, both in inclination and in character, is stayed on God. Your mind does not consider options first, before deciding who to trust, but it sees God as the only one that is worthy of trust. Your mind is stayed on God alone, not seeking temporary residence in a lot of options. God is not a spare tyre, to be used only on emergencies, and completely ignored and forgotten most times.
3. God's peace cannot be defined by the world, because the world does not understand its foundations. Peace that God gives does not shield us from issues, but it gives us calm in the face of the most distressing of circumstances. Don't let the world define what peace means; God has been defining it since the days of Joseph in the prison, the three Hebrew men in the furnace of fire, and Daniel in the lions' den. That is peace - God's presence in the face of the most distressing of circumstances, and joy in the midst of the strongest discomfort.
4. When you hear someone make a promise, you watch out for the capacity, capability and ability of the person promising to fulfil what s/he has promised. God sets out his ability,capacity and capability in these few words-he is the Rock of Ages. That is deep. Long before the problems came, God has been God, and long after the problems would have ceased, and life itself as we know it would have ended, God would always remain God. He can be trusted to keep his promises. His time of favour is here.