In him our hearts rejoice,
for we trust in his holy name.
Trust and thankfulness are joined at the hip. We have both, or we have neither.
Trust and thankfulness are the outgrowth of our conviction that some things are unquestionably and irrevocably true.
If you believe it is unquestionably and irrevocably true that God loves you (1 Jn. 3:1) and that his grace is sufficient for you (2 Cor. 12:9), you possess a level of trust and thankfulness that equips you to face anything that comes at you. You are able to trust him with all your heart (Prov. 3:5), and give thanks in all circumstances (1 Thess. 5:18).
Over and over throughout this day say . . .
I trust you, Lord. Thank you, Lord. I trust you, Lord. Thank you, Lord. I trust you, Lord. Thank you, Lord.
Trust is your instrument.
Thankfulness is your song.