Can I just sit and have my mind on Christ? Not praying or singing?
Absolutely. Php 4:8(8) Finally, brethren, whatsoever things are true, whatsoever things are honest, whatsoever things are just, whatsoever things are pure, whatsoever things are lovely, whatsoever things are of good report; if there be any virtue, and if there be any praise, think on these things.1Ti 4:13-16(13) Till I come, give attendance to reading, to exhortation, to doctrine.(14) Neglect not the gift that is in thee, which was given thee by prophecy, with the laying on of the hands of the presbytery.(15) Meditate upon these things; give thyself wholly to them; that thy profiting may appear to all.(16) Take heed unto thyself, and unto the doctrine; continue in them: for in doing this thou shalt both save thyself, and them that hear thee.Think about how much time you have spent in the past thinking about the things that are worrying you, upsetting you, bothering you, etc. Choose instead to stay your mind on Christ and on His word. Another thing to consider is God's desire to commune with you. Prayer is dialogue and God desires to and will speak to you. However it is hard for you to hear if you are always speaking or singing. That is not to say that God cannot speak to you while you are singing, but often it is good to simply be silent before Him.
The Scripture tells us that when we are in need we pray, when our needs are met, we give thanks and sing praises. And yes, we can even take a walk in a lonely place and become quiet and still.
I believe it is very beneficial to dwell on a truth and just enjoy it and meditate on it for a while. It's too easy to just wander from truth to truth and subject to subject and never enter deeply into God's truth. This wandering produces Christians that are "an inch deep and a mile wide".God dwells in the Holy of Holies, our inmost being, there is rest and peace there. I think quiet adoration is completely appropriate. Oh how great a struggle this stillness is though. It is a habit that must be worked out carefully. I don't claim to have attained but by God's grace I'm learning.In Christ,Ron