Psalms 138:1
1I will give you thanks with my whole heart. Before the gods, I will sing praises to you.
Wesley: before the gods—kings and princes. Whole-heart thanks refuses double speech.
Praise is public and sincere. Give thanks where the powerful can hear; lip-service without the heart is not this verse.
Calvin: whole heart means sincere, not double; praise of a public kind before angels (or an honored assembly) as in a heavenly theater.
Gratitude rises from distinguishing mercies. Hypocrisy empties thanks; sincerity matches the God who helped.