Think of all this, my Brethren, and rouse yourselves, and run forward with a good courage on your way towards heaven. Be not weary in well-doing, for in due season we shall reap, if we faint not. Strive to enter in at the strait gate. Strive to get holier and holier every day, that you may be worthy to stand before the Son of Man. Pray God to teach you His will, and to lead you forth in the right way, because of your enemies. Submit yourselves to His guidance, and you will have comfort given you, according to your day, and peace at the last. [1] Ezek. xxxiii. 11. Isa. v. 4. [2] Eccles. xxiv. 21. [3] Isa. xxv. 6. [4] Isa. lxi. 1-3. [5] Hos. xiv. 5-7. [6] Ps. lxxxi. 13-16. [7] Ps. iv. 7. [8] Ps. xvi. 6. [9] Ps. xix. 10. [10] Ps. xxviii. 7. [11] Ps. lxv. 4. [12] Easter. [13] 1 John iii. 2. [14] Rev. i. 14-16. [15] Wisd. v. 2-5. SERMON XV. Mental Prayer. "_Pray without ceasing._"--1 Thess. v. 17. There are two modes of praying mentioned in Scripture; the one is prayer at set times and places, and in set forms; the other is what the text speaks of,--continual or habitual prayer. The former of these is what is commonly called prayer, whether it be public or private. The other kind of praying may also be called holding communion with God, or living in God's sight, and this may be done all through the day, wherever we are, and is commanded us as the duty, or rather the characteristic, of those who are really servants and friends of Jesus Christ. These two kinds of praying are also natural duties. I mean, we should in a way be bound to attend to them, even if we were born in a heathen country and had never heard of the Bible. For our conscience and reason would lead us to practise them, if we did but attend to these divinely-given informants. I shall here confine myself to the consideration of the latter of the two, habitual or inward prayer, which is enjoined in the text, with the view of showing what it is, and how we are to practise it; and I shall speak of it, first, as a natural duty, and then as the characteristic of a Christian. 1. At first sight, it may be difficult to some persons to understand what is meant by praying always. Now consider it as a natural duty, that is, a duty taught us by natural reason and religious feeling, and you will soon see what it consists in.