Mosiah 18: 9; Doctrine and Covenants 30: 8; 31: 3-5; 32: 1, 5; 35: 13-15, 24

What are the things the Lord asks you to do and what are His promises as you share the gospel?

"9 Yea, and are willing to mourn with those that mourn; yea, and comfort those that stand in need of comfort, and to stand as witnesses of God at all times and in all things, and in all places that ye may be in, even until death, that ye may be redeemed of God, and be numbered with those of the first resurrection, that ye may have eternal life—" (Mosiah 18: 9)

"8 Wherefore, give heed unto these things and be diligent in keeping my commandments, and you shall be blessed unto eternal life. Amen." (Doctrine and Covenants 30: 8)

"3 Lift up your heart and rejoice, for the hour of your mission is come; and your tongue shall be loosed, and you shall declare glad tidings of great joy unto this generation.

4 You shall declare the things which have been revealed to my servant, Joseph Smith, Jun. You shall begin to preach from this time forth, yea, to reap in the field which is white already to be burned.

5 Therefore, thrust in your sickle with all your soul, and your sins are forgiven you, and you shall be laden with sheaves upon your back, for the laborer is worthy of his hire. Wherefore, your family shall live." (Doctrine and Covenants 31: 3-5)

"1 And now concerning my servant Parley P. Pratt, behold, I say unto him that as I live I will that he shall declare my gospel and learn of me, and be meek and lowly of heart." (Doctrine and Covenants 32: 1)

"5 And they shall give heed unto these words and trifle not, and I will bless them. Amen." (Doctrine and Covenants 32: 5)

"13 Wherefore, I call upon the weak things of the world, those who are unlearned and despised, to thresh the nations by the power of my Spirit;

14 And their arm shall be my arm, and I will be their shield and their buckler; and I will gird up their loins, and they shall fight manfully for me; and their enemies shall be under their feet; and I will let fall the sword in their behalf, and by the fire of mine indignation will I preserve them.

15 And the poor and the meek shall have the gospel preached unto them, and they shall be looking forth for the time of my coming, for it is nigh at hand—" (Doctrine and Covenants 35: 13-15)

"24 Keep all the commandments and covenants by which ye are bound; and I will cause the heavens to shake for your good, and Satan shall tremble and Zion shall rejoice upon the hills and flourish;" (Doctrine and Covenants 35: 24)

And here's the beginning part of the commentary entitled: "I am called to be a witness of Jesus Christ." : 

"Whether or not you have a formal calling as a missionary, you can be a witness of Jesus Christ “at all times, and in all things, and in all places” (Mosiah 18:9). As you study Doctrine and Covenants 30–36, record what you learn about your opportunities to share the gospel. You could make a list of things the Lord asks of you and another list of promises the Lord makes as you share the gospel (for example, see Doctrine and Covenants 30:8; 31:3–5; 32:1, 5; 35:13–15, 24). You could also look for principles that can help you share the gospel. What do you find that inspires you to “declare glad tidings of great joy”? (Doctrine and Covenants 31:3)."

I am indeed a witness of Jesus Christ "at all times, and in all things, and in all places" even though I am not given a formal calling as a full-time missionary. I did serve as a full-time missionary for 18 months three decades ago. And so I've been a returned missionary for many years now. Having filled the term as a full-time missionary doesn't mean that my being a witness of Jesus Christ is already over. I'm still a witness of Jesus Christ even though I stopped wearing my name tag. 

Listing here what I learned about my opportunities to share the gospel: 

What the Lord Asks Me

• Be willing to mourn with those that mourn; yea, and comfort those that stand in need of comfort, and to stand as witnesses of God at all times and in all things, and in all places
• Give heed unto these things and be diligent in keeping my commandments
• Lift up your heart and rejoice...
• Declare glad tidings of great joy unto this generation
• Thrust in your sickle with all your soul
• Declare my gospel and learn of me, and be meek and lowly of heart
• Give heed unto these words and trifle not
• Thresh the nations by the power of my Spirit
• Keep all the commandments and covenants by which ye are bound

The Lord's Promises As I Share the Gospel

• Ye may be in, even until death, that ye may be redeemed of God, and be numbered with those of the first resurrection, that ye may have eternal life
• You shall be blessed unto eternal life
• Your tongue shall be loosed
• Your sins are forgiven you
• You shall be laden with sheaves upon your back
• Your family shall live
• I will bless you
• Your arm shall be my arm, and I will be your shield and your buckler; and I will gird up your loins, and you shall fight manfully for me; and your enemies shall be under your feet; and I will let fall the sword in your behalf, and by the fire of mine indignation will I preserve you
• I will cause the heavens to shake for your good
• Satan shall tremble and Zion shall rejoice upon the hills and flourish

All the Lord's promises I found and listed here truly inspire me to "declare glad tidings of great joy". The promises that "Your tongue shall be loosed","I will preserve you", "I will cause the heavens to shake for your good", and "Your family shall live" especially inspire me. These promises are so comforting and mean a lot to me.