Our requests and prayers are to be presented with thanksgiving, every time we talk to our Father. Prayer is not just asking for things, it is an ongoing communication with God, always acknowledged His presence. God is not anxious about anything, He is in control over it all! We should desire the peace that our Father has, trusting His control over all. We must also be careful what we think on, as Christians, we are not allowed to just "think", we need to scrutinize everything we think on.