According to the American Psychological Association, assertiveness is defined as an adaptive style of communication in which individuals express their feelings and needs directly, while maintaining respect for others. Assertiveness is a positive, constructive way of relating. It comes from a desire to build people up rather than tear them down. Assertiveness involves openly stating your needs, wants, feelings, and opinions, recognizing that they are relevant and worthy of being heard. Jesus said to love others as you love yourself: assertiveness values both love for others and love for yourself. When you relate assertively with others, you show that you love and value them as God does. When you respect other people's needs, wants, feelings, and opinions, you treat them assertively without resorting to pressure, threats, manipulation, hostility, or other passive or aggressive approaches to relating.

Knowing what assertiveness is can help us understand what assertiveness is not. Assertiveness is not passive. Passive behavior is when a person holds back from expressing his or her needs, wants, feelings, and opinions. The passive person is reluctant to make decisions, hold any particular position, or take appropriate action. Instead, a passive person often goes along with the wishes of others regardless of what he or she personally wants or what is in his or her best interest. Assertiveness is also not aggressive. Aggressive behavior is when a person relates in a forceful, harsh, or controlling manner. The person puts his or her own needs, wants, feelings, and opinions above those of others and may use demands, insults, sarcasm, manipulation, and other tactics to get his or her own way. A subtle form of aggressive behavior that can also be hurtful is passive aggressive behavior. Passive aggressive behavior is when a person uses covert, hidden, or indirect means of opposition to get his or her way. While on the surface appearing compliant, the person uses stubbornness, pouting, excessive rigidity, veiled criticism, or other stealthy means to undermine the decisions or actions of others.
 
How do you go about becoming an assertive person if your past default behavior has been more passive or aggressive in nature?

Decide Whether to be Assertive
As you dip your toes into assertive waters, the first step is to decide whether the situation calls for assertiveness.  Here are five key questions to help you make that determination:
1. Is this a real problem - or is it a preference or an inconvenience?
2. Is this the right time (now or later) and/or place (publicly or privately) to respond assertively?
3. What are my chances of at least a small measure of success initially? Some issues will take time to resolve.
4. Am I willing to invest time and energy to make the changes?
5. Will I stay relatively calm while I try new, assertive behaviors, not letting fears or anxieties overwhelm me?

Decide What to Say  
If you have answered “yes” to most or all the questions above, the next step is deciding what to say. It’s important to say something rather than nothing. Do not wait for an ideal set of circumstances or the perfect opening. Then simply be honest. Say exactly what you want and need to say to get your point across. As you do this be sure to use “I” messages or “I want” statements rather than “you” statements. By focusing on “I” statements, you will be able to avoid labeling, sarcasm (passive aggressive), or name-calling (aggressive). Try to be as concise as possible so that your assertive message doesn’t get lost in a long-winded explanation and don't apologize for asserting yourself. Remember that you are likely developing a new pattern of communicating, and that doesn’t happen overnight.  Also realize that other people are used to you relating in a specific way and this will likely be an unexpected change for them as well. Be as consistent and persistent as necessary.

Decide What to Do
As you consider your words, it’s equally important to convey a consistent message through body language so that the other person does not get mixed messages. Be sure to look the way you feel. It is better to look serious or angry, than deliver a difficult message with a smile. It is perfectly fine to use assertive gestures that flow naturally. Assertive gestures, however, do not include pointing at the other person (aggressive) or wringing your hands (passive). Be aware of your physical position by having an open posture, facing the other person squarely, and maintaining good eye contact. Speak clearly and pay close attention to the tone of your voice; how you speak is as important as what you say. Then listen - really listen. If assertive communication is about loving and valuing others while also loving and valuing yourself, then listening is not separate from assertive communication: It is part of it.

Jesus was Assertive
Some people believe that Jesus was passive. His use of parables could be construed as indirect, passive communication. And His Sermon on the Mount describes righteousness as meek and peaceful (Matt. 5:5,9) and gives directives to “turn the other cheek” (Matt. 5:39). Indeed, there were times when Jesus assertively chose to be passive. Others believe that Jesus was aggressive. Would a passive person say, “I did not come to bring peace, but a sword” or over-turn the tables of the money-changers (Matt. 21:12)? Yes, there were also times when Jesus assertively took an aggressive approach in communicating. Yet, in His every day, face-to-face interactions with people, he communicated assertively, showing them love and compassion, while at the same time calling them to sin no more.
While assertive communication may not feel comfortable for many of us, we have a Perfect example to follow. As Christians trying to look more like Jesus each day, let us choose assertiveness as the default way we love and communicate with others.

Source: Koch, Ruth N. & Haugk, Kenneth C. Speaking the Truth in Love: How to be an Assertive Christian. Stephen Ministries, 2018.