Heavy lifting requires, not only strength, but also endurance. It requires that you pace yourself, and determine how long you will need to carry the weight. If you fail to plan appropriately, you may have to nurse an unexpected injury. Being among the chosen in the kingdom of God is similar to the art of heavy lifting. You need to plan the days ahead, know your strengths and weaknesses, and make appropriate provisions for any contingencies.
Most importantly, you need to count the costs of being in the kingdom. It must be more important to you than anything the devil might use to entice you. The Lord God Almighty is a jealous God. The Lord God Almighty is a God who sees your weaknesses, and knows that you can overcome them.