'Pray for' in the Bible

Samuel said, "Gather all Israel to Mizpah, and I will pray for you to Yahweh."

All the people said to Samuel, "Pray for your servants to Yahweh your God, that we not die; for we have added to all our sins [this] evil, to ask us a king."

Moreover as for me, far be it from me that I should sin against Yahweh in ceasing to pray for you: but I will instruct you in the good and the right way.