Speaking about man's death, Ecclesiastes 12:7 states: "The dust [of his body] returns to the earth just as it happened to be and the spirit itself returns to the true God who gave it." When the spirit, or life-force, leaves the body, the body dies and returns to where it came from-the earth. Comparably, the life-force returns to where it came from-God. (Job 34:14, 15; Psalm 36:9) This does not mean that the life-force actually travels to heaven. Rather, it means that for someone who dies, any hope of future life rests with Jehovah God. His life is in God's hands, so to speak. Only by God's power can the spirit, or life-force, be given back so that a person may live again.
Regarding the statement in bold, what Biblical basis they used to say that it doesnt mean that our spirits travels to heaven?