And she said, “See, your sister-in-law has gone back to her people and to her gods; return after your sister-in-law.” But Ruth said, “Do not urge me to leave you or to return from following you. For where you go I will go, and where you lodge I will lodge. Your people shall be my people, and your God my God. Where you die I will die, and there will I be buried. May the LORD do so to me and more also if anything but death parts me from you.” And when Naomi saw that she was determined to go with her, she said no more. (Ruth 1:15-18)
See Ruth's resolution, and her good affection to Naomi. Orpah was loth to part from her; yet she did not love her well enough to leave Moab for her sake. Thus, many have a value and affection for Christ, yet come short of salvation by him, because they will not forsake other things for him. They love him, yet leave him, because they do not love him enough, but love other things better.
Ruth is an example of the grace of God, inclining the soul to choose the better part. Naomi could desire no more than the solemn declaration Ruth made. See the power of resolution; it silences temptation. Those that go in religious ways without a steadfast mind, stand like a door half open, which invites a thief; but resolution shuts and bolts the door, resists the devil and forces him to flee.
From Matthew Henry Concise Commentary