To have a humble and kind demeanor which calm another's anger; the ability to take unkind remarks with good nature. The ability to bear reproaches and slights, not easily provoked to anger, free from bitterness and contentiousness, having tranquility and stability in the spirit.

To be gentle is to live on the side of forgiveness rather than on the side of anger.
The Greek language in which the New Testament was first written defines gentleness as power under control. It is illustrated by a horse that has been tamed—strong and powerful, yet under control.

To be gentle in Christ is to have your anger and emotions under His control. One who is walking by the Spirit is going to be a gentle person even in the most trying circumstances through humility coupled with the strength to control one's behavior.

2 Samuel 22:36

"Thou hast also given me the shield of thy salvation; and thy gentleness hath made me great."

Goodness

Goodness is Christian excellence; moral virtue or excellence; showing kindness, generosity, or benevolence. Goodness is the deliberate preference of right to wrong, the firm and persistent resistance of wrong

Ephesians 5:9

"For the fruit of the Spirit is in all goodness and righteousness and truth."

Faith

Confident belief in the truth, value, or trustworthiness of a person, idea, or thing. Belief that does not rest on logical proof.

Hebrews 11:1

Now faith is the substance of things hoped for, the evidence of things not seen.

As Christians, we are justified—or made righteous—by faith. The just person is the one who has been justified, is accepted by God, and lives in harmony with God's will. But for this to happen, we must have the faith of little children.

Galatians 3:24

Wherefore the law was our schoolmaster to bring us unto Christ, that we might be justified by faith.

Romans 5:1

Therefore being justified by faith, we have peace with God through our Lord Jesus Christ.

Meekness

Patient, submissive humbleness; to be gentle-hearted.

Meekness is a quiet, willing submission to God and to others. A meek person has a mild, gentle, non-retaliating spirit. Similar to gentleness, meekness could be called power under control.

There is a big difference between the lion running free in the wilds of Africa and the one responding to the lion tamer at the circus. The lion in the circus has all the same ferocity, energy, power, and strength of the one in the wild, but he is under the control of the lion tamer. The same is true of meekness. No longer does the lion in us seek its own cases and ends; it is submissive to the control of the Master. We don't lose our power; we harness it.

James 1:21

Wherefore lay apart all filthiness and superfluity of naughtiness, and receive with meekness the engrafted word, which is able to save your souls.

1 Timothy 6:11

But thou, O man of God, flee these things; and follow after righteousness, godliness, faith, love, patience, meekness.

Colossians 3:12

Put on therefore, as the elect of God, holy and beloved,...meekness.

Titus 3:2

To speak evil of no man, to be no brawlers, but gentle, shewing all meekness unto all men.

Zephaniah 2:3

...Seek righteousness, seek meekness: it may be ye shall be hid in the day of the Lord's anger.

Temperance

Moderation and self-restraint, as in behavior or expression; restraint or moderation, esp. in yielding to one's appetites or desires

Temperance means self-control. It is control over the whole man (spirit, soul, and body) which enables us to live a victorious life. A person who has self-control is mild and calm, avoids extreme behavior, and exercises self-restraint in both actions and speech. Self-control isn't easy, but it is necessary for operating in the fruit of the Spirit.

We all know that athletes have to stay healthy and fit, with good food and a good workout routine. 1 Corinthians 9:25 tells us that, “And every man that striveth for the mastery is temperate in all things.” As spiritual athletes, we must stay spiritually healthy and fit, feeding ourselves with the healthful Fruits of the Spirit and exercising good temperance.

2 Peter 1:5-8

“And beside this, giving all diligence, add to your faith virtue; and to virtue knowledge; and to knowledge temperance; and to temperance patience; and to patience godliness; and to godliness brotherly kindness; and to brotherly kindness charity. For if these things be I you, and abound, they make you that ye shall neither be barren nor unfruitful in the knowledge of our Lord Jesus Christ. But he that lacketh theses things is blind, and cannot see afar off, and hath forgotten that he was purged from his old sins.”

If you want a strong body, then you have to feed it healthy food.

If you want a strong spirit, then it needs healthy food, too.

How about trying the Fruits of the Spirit?