John Gill Commentary Psalms 119:109

"My soul is continually in my hand; Yet do I not forget thy law." — Psalms 119:109 (ASV)

My soul [is] continually in my hand
In the utmost jeopardy, always exposed to danger, ever delivered unto death; killed all the day long, or liable to be so: this is the sense of the phrase; see (Judges 12:3) (1 Samuel 19:5) ; for what is in a man's hands may easily fall, or be taken out of them: so the Targum, ``my soul is in danger upon the back of my hands continually;'' the Septuagint, Vulgate Latin, Syriac, and Arabic versions, read, "in thy hands"; but wrongly;

yet do I not forget thy law ;
it was written on his heart, and fixed in his mind; he had a true affection for it, and a hearty desire to keep it; and no danger could divert him from his duty; as Daniel, though he carried his life in his hand, yet continued to pray to his God as usual; nor could anything move the Apostle Paul from the doctrine of the Gospel, and preaching it.