Romans 12:12

Rejoicing in hope
Of the glory of God, than the hope of which nothing can make a believer more cheerful in this world; the saints' joy is therefore called the "rejoicing of the hope", ( Hebrews 3:6 ) . This is placed between serving the Lord, and being patient in tribulation; for nothing tends more to animate the people of God to a cheerful serving of him, or to make them more patient under afflictions, than a hope of being for ever with the Lord:

patient in tribulation;
whilst the saints are in this world they must expect tribulation; their way to heaven lies through it; and it becomes them to be patient under it, not murmuring against God, on the one hand, nor reviling of men, on the other.

Continuing instant in prayer:
prayer is needful at all times, but especially in a time of tribulation and distress, whether inward or outward. This should be made without ceasing; saints should watch unto it with all perseverance; men should pray always, and not faint; never give out and over, or be discouraged. This advice is rightly given and placed here, to teach us that we are to go to the throne of grace continually for fresh supplies of grace, and strength to enable us to exercise the grace, and perform the duties exhorted to both in preceding and following verses.