Spiritual disciplines are a type of Deliberate Practice which serve as the primary means of grace through which the Spirit sancitifies the believer and are essential to Transformational Discipleship. A number of these practices can be found throughout Scripture and include things such as: the regular study and memorization of the Scriptures, prayer, fasting, evangelism, corporate worship and fellowship, confession, and accountability.
Scripture does not provide an exhaustive or systematic list of these disciplines, so it is best to think of them as an unbounded set which includes any healthy deliberate practice that effectively forms the believer spiritually. For some, this may inlude a practice like journalling; whereas, for others, it may be walks of solitude. However, not all disciplines are given the same weight within Scripture, which clearly places priority on the Word as God's revelation to man, as well as prayer, fasting, and corporate worship and fellowship with a local body of Christ.
In the West, our understanding of the disciplines is too narrow.
The Western understanding of disciplines is essentially individualistic and does not include very important communal practices. Thus, both the discipline of corporate worship (done with other believers) and the discipline of evangelism (done with those who are not believers) are often left off a list of disciplines altogether in favor of practices that can be accomplished in isolation.
To this end, I appreciate the approach of David Mathis in his work, Habits of Grace. Matthis deals primarily with three means: the word, prayer, and community. I appreciate that he includes biblical community as a major category of discipline. In addition, he considers the communal aspect of both Word and prayer.
These are the most edifying disciplines for me personally.
Of course, this list changes periodically in different seasons of life. However, this is the present snapshot of disciplines that are particularly helpful for me.
First, it must be stated that Scripture is clear on the primary and central importance of study of the Word, prayer, and Christian community. These three are foundational, and in so, should take the "most important" title for all believers. In my own life, I wake early to ensure I can build each day on the platform of the Word and prayer. My day usually starts around 4am with the first hour dedicated to Scripture, prayer, and mindful meditation. In order to continue this deliberate practice, I go to bed early, usually around 9pm. By taking these first hours of the day, I can avoid the interruption that naturally occurs after other people (in my home and outside of it) begin to wake and work. I also begin my day in the word and hopefully set the course for all that will follow. I typically follow a guided reading plan through Scripture. Sometimes I read through the Bible, other times, I slow down to study more intensely a particular book or the Bible. I often make notes, annotate, or engage critically with my reading as well. Prayer is a mix of adoration, those needs I know for our family and others, and the content I have read in Scripture itself. Communally, I place great importance on corporate worship, fellowship, study, and accountablility. Each of these find their best expression in the deep relationships established through participation in the local church.
In addition to these primary practices, a whole range of supplemental disciplines amplify the impact of these when specific practices build upon them as a foundation. In my life, I quickly think of two supplemental disciplines that have an outsized role on my spiritual formation: writing and mindful solitude.
I began writing when I served overseas as a missionary. My schedule allowed for large blocks of time that made contemplation a luxury hard to find here in the States. However, a habit of writing on what I was reading in Scripture with an eye toward application eventually turned into a deliberate practice of publishing articles online. I have continued this practice in every ministry role since that time, and it is immensely edifying. Writing forces the mind to conceptualize and apply what is learned. What is more, writing to teach others refines one's own thoughts even further. I am firm believer in both writing and doing so publicaly, under the scrutiny of others, for mutual edification and accountablility. Writing need not be formally published material, but it should be thoughtful.
More recently, as my responsibilities in ministry increased and our family has grown, I find great value in mindful solitude. My phrasing is intentional. It is solitude in that I seek to be alone with no distraction from other people (that is in person or through some form of media). This means no conversations, no podcasts, no articles, no distraction from my own thoughts. It is mindful in that this solitude is focused time with my own thoughts.Cal Newport talks about this practice in both of his books Deep Work and Digital Minimalism. Newport is not a Christian; however, his work is based in reputable brain science and demonstrates the importance of certain deliberate practices that could be considered spiritual disciplines. This often turns into considering my actions or thinking through future decisions or current problems in light of what I know to be true in Scripture. Sometimes it is evaluative and other times it is simply preaching to myself. Often, this time turns into moments of prayer. For the Christian, solitude is never actually solitude. In order to find this time, I have established routines such as bike riding several times a week or taking intentional walks alone.